Standards. The building blocks of complexity

Without standards, the world as we know it would not be possible. International and supra-cultural standards and norms have been a key factor in engineering, as well as in the development of industrial societies. Despite the obvious successes in electronic and mechanical design, other technological areas present difficulties for the application of standards. In the field of biotechnology and synthetic biology – which aims at studying living things from an engineering perspective – standards are desirable, but whether they can be widely adopted remains to be proved.
 This monograph reviews the sociological and scientific aspects of standardisation and delves into the more problematic fa…

Shedding light on biogas: a transparent reactor triggers the development of a biofilm dominated by Rhodopseudomonas faecalis that holds potential for improved biogas production

AbstractConventional anaerobic digesters intended for the production of biogas usually operate in complete darkness. Therefore, little is known about the effect of light on microbial communities operating in anaerobic digesters. In the present work, we have studied through 16S rRNA gene amplicon Nanopore sequencing and shotgun metagenomic sequencing the taxonomic and functional structure of the microbial community forming a biofilm on the inner wall of a lab-scale transparent anaerobic biodigester illuminated with natural sunlight. The biofilm was composed of microorganisms involved in the four metabolic processes needed for biogas production. The biofilm proved surprisingly rich in Rhodops…

Microbial communities involved in biogas production exhibit high resilience to heat shocks

We report here the impact of heat-shock treatments (55 and 70 °C) on the biogas production within the acidification stage of a two-stage reactor system for anaerobic digestion and biomethanation of grass. The microbiome proved both taxonomically and functionally very robust, since heat shocks caused minor community shifts compared to the controls, and biogas yield was not decreased. The strongest impact on the microbial profile was observed with a combination of heat shock and low pH. Since no transient reduction of microbial diversity occured after the shock, biogas keyplayers, but also potential pathogens, survived the treatment. All along the experiment, the heat-resistant bacterial prof…

Chemically Stressed Bacterial Communities in Anaerobic Digesters Exhibit Resilience and Ecological Flexibility

Anaerobic digestion is a technology known for its potential in terms of methane production. During the digestion process, multiple metabolites of high value are synthesized. However, recent works have demonstrated the high robustness and resilience of the involved microbiomes; these attributes make it difficult to manipulate them in such a way that a specific metabolite is predominantly produced. Therefore, an exact understanding of the manipulability of anaerobic microbiomes may open up a treasure box for bio-based industries. In the present work, the effect of nalidixic acid, γ-aminobutyric acid (GABA), and sodium phosphate on the microbiome of digested sewage sludge from a water treatmen…

Microbial Diversity in the Midguts of Field and Lab-Reared Populations of the European Corn Borer Ostrinia nubilalis

Background: Insects are associated with microorganisms that contribute to the digestion and processing of nutrients. The European Corn Borer (ECB) is a moth present world-wide, causing severe economical damage as a pest on corn and other crops. In the present work, we give a detailed view of the complexity of the microorganisms forming the ECB midgut microbiota with the objective of comparing the biodiversity of the midgut-associated microbiota and explore their potential as a source of genes and enzymes with biotechnological applications. Methodological/Principal Findings: A high-throughput sequencing approach has been used to identify bacterial species, genes and metabolic pathways, parti…

¿Biología o ingeniería? [Ressenya]

Reseña del libro "Biology is technology" de Robert H. Carlson, Harvard University Press, Cambridge (Massachusetts), 2010, 279 pp.

Microbial communities of the Mediterranean rocky coast: ecology and biotechnological potential

AbstractMicrobial communities from harsh environments hold great promise as sources of biotechnologically-relevant strains. In the present work, we have deeply characterized the microorganisms from three different rocky locations of the Mediterranean coast, an environment characterised by being subjected to harsh conditions such as high levels of irradiation and large temperature and salinity fluctuations. Through culture-dependent and culture-independent techniques, we have retrieved a complete view of the ecology and functional aspects of these communities and assessed the biotechnological potential of the cultivable microorganisms. A culture-independent approach through high-throughput 1…

Correlation between serovars of Bacillus thuringiensis and type I beta-exotoxin production.

beta-Exotoxin is a thermostable metabolite produced by some strains of Bacillus thuringiensis. Because of vertebrate toxicity, most commercial preparations of B. thuringiensis are prepared from isolates that do not produce beta-exotoxin. The aim of the present study was to find out the possible relationship between serovars of B. thuringiensis and beta-exotoxin production. A specific HPLC assay for type I beta-exotoxin has been used to detect this exotoxin in supernatants from final whole cultures of 100 strains belonging to four serovars of B. thuringiensis: thuringiensis, kurstaki, aizawai, and morrisoni. For each serovar, 25 strains randomly chosen from two Spanish collections were analy…

Kineococcus vitellinus sp. nov., Kineococcus indalonis sp. nov. and Kineococcus siccus sp. nov., isolated nearby the Tabernas desert (Almería, Spain)

This article belongs to the Section Environmental Microbiology.

Synthetic microbiology as a source of new enterprises and job creation: a Mediterranean perspective

Peer reviewed

Rice straw management: the big waste

Rice is one of the major foods, with consumption per capita of 65 kg per year, accounting for 20% of global ingested calories. Rice production is expected to increase significantly in the near future in order to feed the rising human population. Today, paddy rice culture produces 660 million tons of rice, along with 800 million dry tons of agricultural residues, mainly straw. This biomass is managed predominantly through rice straw burning (RSB) and soil incorporation strategies. RSB leads to significant air pollution and has been banned in some regions, whereas stubble and straw incorporation into wet soil during land preparation is associated with enhanced methane emissions. Therefore, bo…

MOESM7 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 7: Table S7. Number of reads and mean length of reads for bacteria from the methane stages.

The wasted chewing gum bacteriome

Here we show the bacteriome of wasted chewing gums from five different countries and the microbial successions on wasted gums during three months of outdoors exposure. In addition, a collection of bacterial strains from wasted gums was set, and the biodegradation capability of different gum ingredients by the isolates was tested. Our results reveal that the oral microbiota present in gums after being chewed, characterised by the presence of species such as Streptococcus spp. or Corynebacterium spp., evolves in a few weeks to an environmental bacteriome characterised by the presence of Acinetobacter spp., Sphingomonas spp. and Pseudomonas spp. Wasted chewing gums collected worldwide contain …

MOESM8 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 8: Table S8. Number of reads and mean length of reads for archaea from the methane stages.

Complete Genome Sequence of a New Firmicutes Species Isolated from Anaerobic Biomass Hydrolysis

ABSTRACT A new Firmicutes isolate, strain HV4-6-A5C, was obtained from the hydrolysis stage of a mesophilic and anaerobic two-stage lab-scale leach-bed system for biomethanation of fresh grass. It is assumed that the bacterial isolate contributes to plant biomass degradation. Here, we report a draft annotated genome sequence of this organism.

Polar solar panels: Arctic and Antarctic microbiomes display similar taxonomic profiles

Solar panels located on high (Arctic and Antarctic) latitudes combine the harshness of the climate with that of the solar exposure. We report here that these polar solar panels are inhabited by similar microbial communities in taxonomic terms, dominated by Hymenobacter spp., Sphingomonas spp. and Ascomycota. Our results suggest that solar panels, even on high latitudes, can shape a microbial ecosystem adapted to irradiation and desiccation.

Belnapia mucosa sp. nov. and Belnapia arida sp. nov., isolated from desert biocrust

Two novel Gram-staining-negative, aerobic, cocci-shaped, non-motile, non-spore forming, pink-pigmented bacteria designated strains T6T and T18T, were isolated from a biocrust (biological soil crust) sample from the vicinity of the Tabernas Desert (Spain). Both strains were catalase-positive and oxidase-negative, and grew under mesophilic, neutrophilic and non-halophilic conditions. According to the 16S rRNA gene sequences, strains T6T and T18T showed similarities with Belnapia rosea CGMCC 1.10758T and Belnapia moabensis CP2CT (98.11 and 98.55% gene sequence similarity, respectively). The DNA G+C content was 69.80 and 68.96% for strains T6T and T18T, respectively; the average nucleotide iden…

Are multi-omics enough?

Multi-omic techniques are often seen as the future of microbiome studies. We argue that recent strategies for simplifying complex omic-derived data will need to be combined with improved cultivation techniques to pave the way towards a more targeted approach for understanding microbial communities.

Identification and characterization of the new Bacillus thuringiensis serovars pirenaica (serotype H57) and iberica (serotype H59)

Two new Bacillus thuringiensis strains have been classified by the H antigen of the cells and differentiated by their morphological, biochemical and molecular characteristics. The flagellar agglutination showed that both strains bore specific H antigens which allowed their classification as the new serotypes H57 and H59. The serovar names proposed for the type strains characterized in this work are B. thuringiensis ser. pirenaica, for the H serotype 57, and B. thuringiensis ser. iberica, for the H serotype 59. Further characterization of these strains, by means of SDS-PAGE, Western inmunodetection, plasmid profile and cry-gene identification by polymerase chain reaction, confirmed the origi…

Complete Genome Sequence of a New Clostridium sp. Isolated from Anaerobic Digestion and Biomethanation

Here, we present the genome sequence and annotation of the bacterial strain HV4-5-A1G, a potentially new Clostridium species. Based on its genomic data, this strain may act as a keystone microorganism in the hydrolysis of complex polymers, as well as in the different acidogenesis and acetogenesis steps during anaerobic digestion.

Complete Genome Sequence of “Candidatus Tremblaya princeps” Strain PCVAL, an Intriguing Translational Machine below the Living-Cell Status

ABSTRACT The sequence of the genome of “ Candidatus Tremblaya princeps” strain PCVAL, the primary endosymbiont of the citrus mealybug Planococcus citri , has been determined. “ Ca . Tremblaya princeps” presents an unusual nested endosymbiosis and harbors a gammaproteobacterial symbiont within its cytoplasm in all analyzed mealybugs. The genome sequence reveals that “ Ca . Tremblaya princeps” cannot be considered an independent organism but that the consortium with its gammaproteobacterial symbiotic associate represents a new composite living being.

The Generalist Inside the Specialist: Gut Bacterial Communities of Two Insect Species Feeding on Toxic Plants Are Dominated by Enterococcus sp.

Some specialist insects feed on plants rich in secondary compounds, which pose a major selective pressure on both the phytophagous and the gut microbiota. However, microbial communities of toxic plant feeders are still poorly characterized. Here, we show the bacterial communities of the gut of two specialized Lepidoptera, Hyles euphorbiae and Brithys crini, which exclusively feed on latex-rich Euphorbia sp. and alkaloid-rich Pancratium maritimum, respectively. A metagenomic analysis based on high-throughput sequencing of the 16S rRNA gene revealed that the gut microbiota of both insects is dominated by the phylum Firmicutes, and especially by the common gut inhabitant Enterococcus sp. Staph…

The ten grand challenges of synthetic life

The construction of artificial life is one of the main scientific challenges of the Synthetic Biology era. Advances in DNA synthesis and a better understanding of regulatory processes make the goal of constructing the first artificial cell a realistic possibility. This would be both a fundamental scientific milestone and a starting point of a vast range of applications, from biofuel production to drug design. However, several major issues might hamper the objective of achieving an artificial cell. From the bottom-up to the selection-based strategies, this work encompasses the ten grand challenges synthetic biologists will have to be aware of in order to cope with the task of creating life i…

Effects ofBacillus thuringiensisCry1Ab and Cry3Aa endotoxins on predatory Coleoptera tested through artificial diet-incorporation bioassays

AbstractTraditional approaches to studying the effects of genetically modified (GM) crops on beneficial insects involve either field assays, comparing insect population levels between control and GM crops or tritrophic bioassays with contaminated insects – usually larvae or eggs of Lepidoptera – as preys. Here, we report the results of a bioassay using an artificial diet, suitable for predatory Coleoptera, to supplyBacillus thuringiensis(Bt) solubilized Cry1Ab and Cry3Aa as well as trypsin-activated Cry1Ab toAtheta coriariaandCryptolaemus montrouzieriadults and young larvae ofAdalia bipunctata. Water, solubilization buffer and trypsin-treated solubilization buffer were used as controls. In …

The long journey towards standards for engineering biosystems: Are the Molecular Biology and the Biotech communities ready to standardise?

Standards are the basis of technology: they allow rigorous description and exact measurement of properties, reliable reproducibility and a common “language” that enables different communities to work together. Molecular biology was in part created by physicists; yet, the field did not inherit the focus on the quantitation, the definition of system boundaries and the robust, unequivocal language that is characteristic of the other natural sciences. However, synthetic biology (SynBio) increasingly requires scientific, technical, operational and semantic standards for the field to become a full‐fledged engineering discipline with a high level of accuracy in the design, manufacturing and perfor…

Liquid co-substrates repower sewage microbiomes

AbstractA range of parameters are known to shape the methanogenic communities of biogas-producing digesters and to strongly influence the amount of biogas produced. In this work, liquid and solid fractions of grass biomass were used separately for semicontinuous batch methanation using sewage sludge as seed sludge. During 6 months of incubation, the amount of input COD was increased gradually, and the underlying methanogenic microbiome was assessed by means of microscopy-based automated cell counting and full-length 16S rRNA high-throughput sequencing. In this sense, we prove for the first time the suitability of the ONT™MinION platform as a monitoring tool for anaerobic digestion systems. …

Selecting Microbial Strains from Pine Tree Resin: Biotechnological Applications from a Terpene World

Resin is a chemical and physical defensive barrier secreted by many plants, especially coniferous trees, with insecticidal and antimicrobial properties. The degradation of terpenes, the main components accounting for the toxicity of resin, is highly relevant for a vast range of biotechnological processes, including bioremediation. In the present work, we used a resin-based selective medium in order to study the resin-tolerant microbial communities associated with the galls formed by the moth Retinia resinella; as well as resin from Pinus sylvestris forests, one of the largest ecosystems on Earth and a yet-unexplored source of terpene-degrading microorganisms. The taxonomic and functional di…

The coffee-machine bacteriome: biodiversity and colonisation of the wasted coffee tray leach

AbstractMicrobial communities are ubiquitous in both natural and artificial environments. However, microbial diversity is usually reduced under strong selection pressures, such as those present in habitats rich in recalcitrant or toxic compounds displaying antimicrobial properties. Caffeine is a natural alkaloid present in coffee, tea and soft drinks with well-known antibacterial properties. Here we present the first systematic analysis of coffee machine-associated bacteria. We sampled the coffee waste reservoir of ten different Nespresso machines and conducted a dynamic monitoring of the colonization process in a new machine. Our results reveal the existence of a varied bacterial community…

Assembly methods for nanopore-based metagenomic sequencing: a comparative study

ABSTRACTBackgroundMetagenomic sequencing has lead to the recovery of previously unexplored microbial genomes. In this sense, short-reads sequencing platforms often result in highly fragmented metagenomes, thus complicating downstream analyses. Third generation sequencing technologies, such as MinION, could lead to more contiguous assemblies due to their ability to generate long reads. Nevertheless, there is a lack of studies evaluating the suitability of the available assembly tools for this new type of data.FindingsWe benchmarked the ability of different short-reads and long-reads tools to assembly two different commercially available mock communities, and observed remarkable differences i…

Paving the way for synthetic biology‐based bioremediation in Europe

The Software Crisis of Synthetic Biology

In fifteen years, Synthetic Biology (SB) has moved from proof-of-concept designs to several flagship achievements. Standardisation efforts are still under way, basic engineering concepts such as modularity and orthogonality are still controversial in biology, and making predictions from computer models is still unreliable. A deep characterization in the pattern of re-use of biological blocks in SB has not been attempted to date. We have compared the topological organisation of two different technological networks, one associated to a standard, large-scale software repository and the second provided by the Registry of Standard Biological Parts (RSBP). Our results strongly suggest that softwa…

Pathogenicity of intrathoracically administrated Bacillus thuringiensis spores in Blatta orientalis.

Abstract The ability of Bacillus thuringiensis to produce septicaemia in Periplaneta americana and Blatta orientalis has been investigated. Spores and crystals from several wild-type strains as well as spores of a B. thuringiensis crystal-deficient mutant, were first orally administrated at high doses, and no significant mortality was recorded. Intrathoracic injection of spore suspensions in P. americana revealed that this species is not very susceptible to B. thuringiensis spores. B. orientalis , by contrast, was found to be very susceptible to B. thuringiensis , with a LD 50 of about 35,000 spores, that is similar to that reported on Lepidoptera challenged with parenterally injected B. th…

MOESM3 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 1: Figure S3. SDS-PAGE displaying the protein profiles.

Characterization ofBacillus thuringiensisserovarbolivia(serotype H63), a novel serovar isolated from the Bolivian high valleys

The type strain Bacillus thuringiensis var. bolivia (serotype H63), isolated from the Bolivian high valleys, has been characterized at different levels. Its parasporal crystal has an unusual shape and it is composed of a protein of 155 kDa which shows two bands of 75 and 80 kDa after activation. Analysis by PCR shows the presence of cry1 genes, and amplification with specific primers gave products for cry1 E, cry1 D, cry4 A and cry4 B with sizes different to those expected. Immunoblotting tests showed positive reaction for Cry1 E, Cry3 A, Cry4 A and Cry11 A crystal proteins. The plasmid pattern revealed two large and two small plasmids. Toxicity tests were performed against 14 insects and a…

Ecological Mysteries: is <i>Bacillus thuringiensis</i> a Real Insect Pathogen?

Bacillus thuringiensis ( Bt ) can kill insects and multiply in their bodies, but it can also grow in semi-synthetic media; is found in environments were insects are absent; and has been reported to require midgut-associated bacteria for toxicity. We propose here a novel life cycle for Bt combining insect-based and insect-independent life cycles.

Ammonia removal during leach-bed acidification leads to optimized organic acid production from chicken manure

This work demonstrates the suitability of nitrogen removal during anaerobic acidification in batch configuration for a more efficient pre-treatment of chicken manure prior to anaerobic digestion. High loading rates corresponding to a total nitrogen input between 6.3 and 9.5 g L−1 allowed successful suppression of methanogenic archaea. To eliminate nitrogen, NH3-stripping and MAP (magnesium ammonium phosphate hexahydrate) precipitation were compared. In spite of decreased cell quantities detected using qPCR, removal of nitrogen caused an increase in volatile fatty acid (VFA) formation from 13 to 19%. The highest nitrogen removal during acidification (up to 29%) was achieved with three consec…

Warm and wet: robust lipase-producing bacteria from the indoor environment

Lipases are key biocatalysts with important biotechnological applications. With the aim of isolating robust lipolytic microbial strains, we have analyzed the bacterial communities inhabiting two domestic extreme environments: a thermophilic sauna and a dishwasher filter. Scanning electron microscopy revealed biofilm-forming and scattered microorganisms in the sauna and dishwasher sample, respectively. A culture-independent approach based on 16S rRNA analysis indicated a high abundance of Proteobacteria in the sauna sample; and, a large amount of Proteobacteria, Firmicutes, Cyanobacteria and Actinobacteria in the dishwasher filter. With a culture-dependent approach, we isolated 48 bacterial …

Characterization of Bacillus thuringiensis ser. balearica (Serotype H48) and ser. navarrensis (serotype H50): two novel serovars isolated in Spain.

The novel strains of Bacillus thuringiensis PM9 and NA69, isolated from soil samples in Spain, were classified and characterized in terms of their crystal proteins, plasmid profile, cry genes content, and their toxicological properties against several species of Lepidoptera, Coleoptera, and Diptera. Both strains share morphological and biochemical characteristics with previously described B. thuringiensis strains, although their unique H antigens identify them as two new serotypes. Two new serovar names, B. thuringiensis serovar balearica (H serotype 48) and B. thuringiensis serovar navarrensis (H serotype 50) are proposed for the type strains PM9 and NA69, respectively.

Unveiling Bacterial Interactions through Multidimensional Scaling and Dynamics Modeling

AbstractWe propose a new strategy to identify and visualize bacterial consortia by conducting replicated culturing of environmental samples coupled with high-throughput sequencing and multidimensional scaling analysis, followed by identification of bacteria-bacteria correlations and interactions. We conducted a proof of concept assay with pine-tree resin-based media in ten replicates, which allowed detecting and visualizing dynamical bacterial associations in the form of statistically significant and yet biologically relevant bacterial consortia.

Strategies for Making Life

Synthetic biology is a multifaceted discipline and the pathways towards an artificial cell are diverse. Top-down strategies seek simplification of genomes, their chemical synthesis and transplantation into a cell chassis. In the long term, scientists hope to have genomic platforms to reinvent metabolic networks capable of producing molecules of biotechnological interest. On the other hand, a bottom-up strategy relies on the chemical implementation of fundamental concepts such as self-reproduction, self-replication and self-maintaining systems. In addition to the artificial synthesis of simplified genomes and protocells, some scientists explore xenobiology, or making life as we do not know i…

Complete Genome Sequence of a New Ruminococcaceae Bacterium Isolated from Anaerobic Biomass Hydrolysis

ABSTRACT A new Ruminococcaceae bacterium, strain HV4-5-B5C, participating in the anaerobic digestion of grass, was isolated from a mesophilic two-stage laboratory-scale leach bed biogas system. The draft annotated genome sequence presented in this study and 16S rRNA gene sequence analysis indicated the affiliation of HV4-5-B5C with the family Ruminococcaceae outside recently described genera.

Shedding light on biogas: Phototrophic biofilms in anaerobic digesters hold potential for improved biogas production

Conventional anaerobic digesters intended for the production of biogas usually operate in complete darkness. Therefore, little is known about the effect of light on their microbial communities. In the present work, 16S rRNA gene amplicon Nanopore sequencing and shotgun metagenomic sequencing were used to study the taxonomic and functional structure of the microbial community forming a biofilm on the inner wall of a laboratory-scale transparent anaerobic biodigester illuminated with natural sunlight. The biofilm was composed of microorganisms involved in the four metabolic processes needed for biogas production, and it was surprisingly rich in Rhodopseudomonas faecalis, a versatile bacterium…

What Is Life?

Despite the difficulty of defining a living being, biological sciences have considerably advanced. Today many authors feel the need to revisit the issue of the definition of life, among other reasons, because we are very close to have a second example of life. This life will not be the direct result of more than 3,500 million years of evolution, but the outcome of a project of synthetic biology in a laboratory. The fact that evolution has explored only a small part of the possible may pave the way towards alternative artificial lives. Focusing on the nature of life makes us more critical with the Cartesian comparisons between cells and machines. At the same time, progress in synthetic biolo…

Responsibility and intellectual property in synthetic biology: A proposal for using Responsible Research and Innovation as a basic framework for intellectual property decisions in synthetic biology

Synthetic biology (SynBio) is an engineering view of biotechnology that has the potential to increase the number and industrial utility of biotechnological applications by implementing engineering principles such as standardization and modularity. The boundaries between SynBio, biotechnology, and metabolic engineering are not always clear, but assessing SynBio in a wider sense—that of modeling‐based biotechnology and/or “sophisticated” metabolic engineering—we find that a significant number of applications and research articles have been generated in the past few years [1]. One of the best‐known examples is that of a synthetic pathway for producing artemisinic acid, a precursor to the antim…

MOESM2 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 5: Table S2. Overview of reaction stages and reactor performance.

Beyond archaea: The table salt bacteriome

Commercial table salt is a condiment with food preservative properties by decreasing water activity and increasing osmotic pressure. Salt is also a source of halophilic bacteria and archaea. In the present research, the diversity of halotolerant and halophilic microorganisms was studied in six commercial table salts by culture-dependent and culture-independent techniques. Three table salts were obtained from marine origins: Atlantic Ocean, Mediterranean (Ibiza Island), and Odiel marshes (supermarket marine salt). Other salts supplemented with mineral and nutritional ingredients were also used: Himalayan pink, Hawaiian black, and one with dried vegetables known as Viking salt. The results of…

The iGEM Competition

The international Genetically Engineered Machine (iGEM) competition is a well-known example of synthetic biology and a workbench for the development of heterodox, multidisciplinary and frontier work made by undergraduate students. We review the origin, organization and structure of the competition; we describe how an iGEM team can be set in place, and briefly summarize some of the main milestones and challenges of a competition that is only one decade old. We discuss the links of the competition with the Registry of Standard Biological Parts and the flagship role of iGEM as a very trench of the synthetic biology revolution.

Synthetic Biology in Action

Last decade has witnessed remarkable advances towards the engineering of life. The examples range from the design of an efficient cellular factory for the semi-synthesis of the antimalarial drug artemisinin, to the chemical synthesis of chromosomes, both bacterial and eukaryotic. In parallel, advances in the deep characterization of cell machineries in the simplest cells show that we are very far of fully understanding the regulation of metabolic and genetic circuits. Biological emergent properties and noise may suppose an obstacle for predictive design. Besides the obvious biotechnological benefits of synthetic biology, the path towards the artificial cell will report new insights on the e…

Extremophilic microbial communities on photovoltaic panel surfaces: a two‐year study

Solar panel surfaces can be colonized by microorganisms adapted to desiccation, temperature fluctuations and solar radiation. Although the taxonomic and functional composition of these communities has been studied, the microbial colonization process remains unclear. In the present work, we have monitored this microbial colonization process during 24 months by performing weekly measurements of the photovoltaic efficiency, carrying out 16S rRNA gene high‐throughput sequencing, and studying the effect of antimicrobial compounds on the composition of the microbial biocenosis. This is the first time a long‐term study of the colonization process of solar panels has been performed, and our results…

What Is Synthetic Biology?

Synthetic biology aims at the design and construction of biological devices and systems for useful purposes. From an ideal engineering perspective synthetic biology works from rational design made through a few conceptual pillars, namely abstraction, standardization and modularity. Nevertheless, the combination of our still fragmentary biological knowledge and the messy nature of biological devices are major challenges for engineering life in a predictive manner. It is urgent to build bridges between different disciplines, from biology to engineer and back, to pursue this extraordinary goal of making life.

Microbial Ecology on Solar Panels in Berkeley, CA, United States

Solar panels can be found practically all over the world and represent a standard surface that can be colonized by microbial communities that are resistant to harsh environmental conditions, including high irradiation, temperature fluctuations and desiccation. These properties make them not only ideal sources of stress-resistant bacteria, but also standard devices to study the microbial communities and their colonization process from different areas of Earth. We report here a comprehensive description of the microbial communities associated with solar panels in Berkeley, CA, United States. Cultivable bacteria were isolated to characterize their adhesive capabilities, and UV- and desiccation…

Additional file 1: Table S1. of Standards not that standard

Biobrick parts (Bb1 to Bb6) included in the different DNA constructions tested in this work. Table S2. Proteins displaying statistically significant alterations in their expression levels, as detected by iTRAQ analysis (DOCX 18 kb).

Mealybugs nested endosymbiosis: going into the 'matryoshka' system in Planococcus citri in depth.

Abstract Background In all branches of life there are plenty of symbiotic associations. Insects are particularly well suited to establishing intracellular symbiosis with bacteria, providing them with metabolic capabilities they lack. Essential primary endosymbionts can coexist with facultative secondary symbionts which can, eventually, establish metabolic complementation with the primary endosymbiont, becoming a co-primary. Usually, both endosymbionts maintain their cellular identity. An exception is the endosymbiosis found in mealybugs of the subfamily Pseudoccinae, such as Planococcus citri, with Moranella endobia located inside Tremblaya princeps. Results We report the genome sequencing …

Standards not that standard

There is a general assent on the key role of standards in Synthetic Biology. In two consecutive letters to this journal, suggestions on the assembly methods for the Registry of standard biological parts have been described. We fully agree with those authors on the need of a more flexible building strategy and we highlight in the present work two major functional challenges standardization efforts have to deal with: the need of both universal and orthogonal behaviors. We provide experimental data that clearly indicate that such engineering requirements should not be taken for granted in Synthetic Biology. Electronic supplementary material The online version of this article (doi:10.1186/s1303…

The rose and the name: the unresolved debate on biotechnological terms

The largest survey on the perception of synthetic biology‐related disciplines (Porcar et al., 2019,EMBO Rep 20) recently revealed that the Spanish society does not have a very positive perception of the term synthetic biology. On the other hand, the terms biotechnology and even genetic engineering received relatively higher scores. The issue of nomenclature and perception is a classical one in science perception studies. Synthetic biologists have been debating their neologism (Synthetic Biology, from now on SB) for years. Even in a 2006 blog, Rob Carlson discussed the various labels for the new field, such as intentional biology, constructive biology, natural engineering, synthetic genomics…

What Was Synthetic Biology?

The desire to make life is not new. Mythology and history provide numerous examples of this Promethean longing. Materialist and evolutionist scientists over a century ago were convinced of the possibility and even the need to synthesize living beings to advance the knowledge on the nature and origin of life. The premature synthetic biology attempts by Stephane Leduc and Alfonso L. Herrera reflected the mechanistic ideal in biology of Jacques Loeb. The book “La biologie synthetique” by Leduc (1912) clearly defines the efforts of these pioneers: “Why is it less acceptable to seek how to make a cell than how to make a molecule?” Journalists have presented many advances in biology in the past c…

The Hidden Charm of Life

Synthetic biology is an engineering view on biotechnology, which has revolutionized genetic engineering. The field has seen a constant development of metaphors that tend to highlight the similarities of cells with machines. I argue here that living organisms, particularly bacterial cells, are not machine-like, engineerable entities, but, instead, factory-like complex systems shaped by evolution. A change of the comparative paradigm in synthetic biology from machines to factories, from hardware to software, and from informatics to economy is discussed.

A highly diverse, desert-like microbial biocenosis on solar panels in a Mediterranean city

AbstractMicroorganisms colonize a wide range of natural and artificial environments although there are hardly any data on the microbial ecology of one the most widespread man-made extreme structures: solar panels. Here we show that solar panels in a Mediterranean city (Valencia, Spain) harbor a highly diverse microbial community with more than 500 different species per panel, most of which belong to drought-, heat- and radiation-adapted bacterial genera, and sun-irradiation adapted epiphytic fungi. The taxonomic and functional profiles of this microbial community and the characterization of selected culturable bacteria reveal the existence of a diverse mesophilic microbial community on the …

Words, images and gender

Financial support from the European CSA on biological standardization BIOROBOOST (EU grant number 820699, http://standardsinsynbio.eu) is acknowledged. EMM is funded with a Formacion de Profesorado Universitario (FPU) grant from the Spanish Government (Ministerio de Ciencia, Innovacion y Universidades), with reference FPU17/04184. ALP is a recipient of a Doctorado Industrial fellowship from the Ministerio de Ciencia, Innovacion y Universidades (Spain), with reference DI‐17‐09613.

Eubacteria and archaea communities in seven mesophile anaerobic digester plants in Germany

Background Only a fraction of the microbial species used for anaerobic digestion in biogas production plants are methanogenic archaea. We have analyzed the taxonomic profiles of eubacteria and archaea, a set of chemical key parameters, and biogas production in samples from nine production plants in seven facilities in Thuringia, Germany, including co-digesters, leach-bed, and sewage sludge treatment plants. Reactors were sampled twice, at a 1-week interval, and three biological replicates were taken in each case. Results A complex taxonomic composition was found for both eubacteria and archaea, both of which strongly correlated with digester type. Plant-degrading Firmicutes as well as Bacte…

MOESM1 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 4: Table S1. Description of the used seed sludge.

Biological Standards and Biosecurity: The Unexplored Link

AbstractThe issue of standardisation in Synthetic Biology has important implications at both the technical and governance levels. At the former, standardisation in biology (a still-ongoing process) is expected to exponentially increase the potential of synthetic biology by democratising, easing and expanding our ability to engineer life. Indeed, it has to be stressed that Synthetic Biology is -or at least aims at being- a fully engineering discipline. And engineering, from industrial to electronics, largely relies on standards. A standard is a part, piece, device or procedure with well-established properties, and which can reliably be used in a broad range of industrial applications. Standa…

Towards a microbial thermoelectric cell.

Microbial growth is an exothermic process. Biotechnological industries produce large amounts of heat, usually considered an undesirable by-product. In this work, we report the construction and characterization of the first microbial thermoelectric cell (MTC), in which the metabolic heat produced by a thermally insulated microbial culture is partially converted into electricity through a thermoelectric device optimized for low ΔT values. A temperature of 41°C and net electric voltage of around 250–600 mV was achieved with 1.7 L baker’s yeast culture. This is the first time microbial metabolic energy has been converted into electricity with an ad hoc thermoelectric device. These results might…

Vida fabricada

Des que la biologia es va secularitzar i inicia l’escrutini molecular de la vida, la possibilitat de la sintesi artificial de cel·lules vivents en un laboratori fou palpable. La biologia sintetica contemporania aspira a dissenyar i fabricar noves formes de vida amb la intencio d’obtenir beneficis socials i economics, tot i que no s’ha de descartar que tambe obtindrem, per la via sintetica, recompenses cientifiques en termes d’una major comprensio de la complexitat biologica a les quals no podriem accedir per la via analitica. Es clar, per tant, que biologia sintetica es un terme que desperta expectatives, pero no es menys cert que tambe provoca inquietud. El Forum Economic Mundial ha situat…

Aequorin-expressing yeast emits light under electric control

In this study, we show the use of direct external electrical stimulation of a jellyfish luminescent calcium-activated protein, aequorin, expressed in a transgenic yeast strain. Yeast cultures were electrically stimulated through two electrodes coupled to a standard power generator. Even low (1.5. V) electric pulses triggered a rapid light peak and serial light pulses were obtained after electric pulses were applied periodically, suggesting that the system is re-enacted after a short refraction time. These results open up a new scenario, in the very interphase between synthetic biology and cybernetics, in which complex cellular behavior might be subjected to electrical control.

A lab in the field: applications of real-time, in situ metagenomic sequencing

High-throughput metagenomic sequencing is considered one of the main technologies fostering the development of microbial ecology. Widely used second-generation sequencers have enabled the analysis of extremely diverse microbial communities, the discovery of novel gene functions, and the comprehension of the metabolic interconnections established among microbial consortia. However, the high cost of the sequencers and the complexity of library preparation and sequencing protocols still hamper the application of metagenomic sequencing in a vast range of real-life applications. In this context, the emergence of portable, third-generation sequencers is becoming a popular alternative for the rapi…

Art‐omics: multi‐omics meet archaeology and art conservation

Summary Multi‐omics can informally be described as the combined use of high‐throughput techniques allowing the characterization of complete microbial communities by the sequencing/identification of total pools of biomolecules including DNA, proteins or metabolites. These techniques have allowed an unprecedented level of knowledge on complex microbial ecosystems, which is having key implications in land and marine ecology, industrial biotechnology or biomedicine. Multi‐omics have recently been applied to artistic or archaeological objects, with the goal of either contributing to shedding light on the original context of the pieces and/or to inform conservation approaches. In this minireview,…

Engineering Bacteria to Form a Biofilm and Induce Clumping in Caenorhabditis elegans

Bacteria are needed for a vast range of biotechnological processes, which they carry out either as pure cultures or in association with other bacteria and/or fungi. The potential of bacteria as biofactories is hampered, though, by their limited mobility in solid or semisolid media such as agricultural or domestic waste. This work represents an attempt toward overcoming this limitation by associating bacterial biotechnological properties with the transport ability of the nematode Caenorhabditis elegans. We report here biofilm formation on C. elegans by engineered Escherichia coli expressing a Xhenorhabdus nematophila adhesion operon and induction of nematode social feeding behavior (clumping…

Thermoelectric Heat Exchange and Growth Regulation in a Continuous Yeast Culture

We have designed a thermoelectric heat exchanger (TEHE) for microbial fermentations that is able to produce electric power from a microbial continuous culture using the intrinsic heat generated by microbial growth. While the TEHE was connected, the system proved able to stably self-maintain both the temperature and the optical density of the culture. This paves the way toward a more sustainable operation of microbial fermentations, in which energy could be saved by converting part of the metabolic heat into usable electric power.

A round trip to the desert: In situ nanopore sequencing informs targeted bioprospecting

Bioprospecting expeditions are often performed in remote locations, in order to access previously unexplored samples. Nevertheless, the actual potential of those samples is only assessed once scientists are back in the laboratory, where a time-consuming screening must take place. This work evaluates the suitability of using Nanopore sequencing during a journey to the Tabernas Desert (Spain) for forecasting the potential of specific samples in terms of bacterial diversity and prevalence of radiation- and desiccation-resistant taxa, which were the target of the bioprospecting activities. Samples collected during the first day were analyzed through 16S rRNA gene sequencing using a mobile labor…

Molecular and Insecticidal Characterization of a Cry1I Protein Toxic to Insects of the Families Noctuidae, Tortricidae, Plutellidae, and Chrysomelidae

ABSTRACT The most notable characteristic of Bacillus thuringiensis is its ability to produce insecticidal proteins. More than 300 different proteins have been described with specific activity against insect species. We report the molecular and insecticidal characterization of a novel cry gene encoding a protein of the Cry1I group with toxic activity towards insects of the families Noctuidae, Tortricidae, Plutellidae, and Chrysomelidae. PCR analysis detected a DNA sequence with an open reading frame of 2.2 kb which encodes a protein with a molecular mass of 80.9 kDa. Trypsin digestion of this protein resulted in a fragment of ca. 60 kDa, typical of activated Cry1 proteins. The deduced sequen…

Bioprospecting challenges in unusual environments

Editorial: The microbiome as a source of new enterprises and job creation.

Towards light-mediated sensing of bacterial comfort

Abstract Bacterial comfort is central to biotechnological applications. Here, we report the characterization of different sensoring systems, the first step within a broader synthetic biology-inspired light-mediated strategy to determine Escherichia coli perception of environmental factors critical to bacterial performance. We did so by directly ‘asking’ bacterial cultures with light-encoded questions corresponding to the excitation wavelength of fluorescent proteins placed under the control of environment-sensitive promoters. We built four genetic constructions with fluorescent proteins responding to glucose, temperature, oxygen and nitrogen; and a fifth construction allowing UV-induced exp…

Effects of Bacillus thuringiensis δ-Endotoxins on the Pea Aphid ( Acyrthosiphon pisum )

ABSTRACT Four Bacillus thuringiensis δ-endotoxins, Cry3A, Cry4Aa, Cry11Aa, and Cyt1Aa, were found to exhibit low to moderate toxicity on the pea aphid, Acyrthosiphon pisum , in terms both of mortality and growth rate. Cry1Ab was essentially nontoxic except at high rates. To demonstrate these effects, we had to use exhaustive buffer-based controls.

Out of the Abyss: Genome and Metagenome Mining Reveals Unexpected Environmental Distribution of Abyssomicins.

AbstractNatural products have traditionally been discovered through the screening of culturable microbial isolates from all sort of environments. The sequencing revolution allowed the identification of dozens of biosynthetic gene clusters (BGCs) within single bacterial genomes, either from cultured or uncultured strains. However, we are still far from fully exploiting the microbial reservoir, as most of the species are non-model organisms with complex regulatory systems and yet recalcitrant to be engineered. Today, genomic and metagenomic data produced by laboratories worldwide covering the most different natural and artificial environments on Earth, are an invaluable source of raw informat…

High Culturable Bacterial Diversity From a European Desert: The Tabernas Desert.

One of the most diverse ecological niches for microbial bioprospecting is soil, including that of drylands. Drylands are one of the most abundant biomes on Earth, but extreme cases, such as deserts, are considered very rare in Europe. The so-called Tabernas Desert is one of the few examples of a desert area in continental Europe, and although some microbial studies have been performed on this region, a comprehensive strategy to maximize the isolation of environmental bacteria has not been conducted to date. We report here a culturomics approach to study the bacterial diversity of this dryland by using a simple strategy consisting of combining different media, using serial dilutions of the n…

iGEM 2.0—refoundations for engineering biology

A Bacillus thuringiensis strain producing epizootics on Plodia interpunctella: A case study

Abstract After several disease outbreaks in laboratory cultures of pyralid moths in Tabriz University, Iran, during 2004 and 2005, a new Bacillus thuringiensis aizawai strain EF495116 (BTA) was isolated from a dead Plodia interpunctella larva. A complete characterization of the strain was performed, including serological identification, protein and plasmid pattern determination, a PCR-based identification of virulence-related genes, nucleotide sequence analysis of the 16S rDNA and gyrB genes (in order to find out relationships between the species with other virulent Bacillus pathogens), and biological activity assays. These studies revealed that BTA produced a major parasporal protein band …

Confidence, tolerance, and allowance in biological engineering: The nuts and bolts of living things

The emphasis of systems and synthetic biology on quantitative understanding of biological objects and their eventual re-design has raised the question of whether description and construction standards that are commonplace in electric and mechanical engineering are applicable to live systems. The tuning of genetic devices to deliver a given activity is generally context-dependent, thereby undermining the re-usability of parts, and predictability of function, necessary for manufacturing new biological objects. Tolerance (acceptable limits within the unavoidable divergence of a nominal value) and allowance (deviation introduced on purpose for the sake of flexibility and hence modularity, i.e. …

Bacteria from acidic to strongly alkaline insect midguts: Potential sources of extreme cellulolytic enzymes

Abstract Bacterial isolates from the European Corn Borer (ECB) Ostrinia nubilalis and the coleopteran Colorado Potato Beetle (CPB) Leptinotarsa decemlineata midguts were identified and characterized. Twenty-four colonies, selected on solid media with cellulose as the sole carbon source and pH values ranging from 5 to 12, were identified through 16S sequencing as members of the genera Acinetobacter , Comamonas , Klebsiella , Microbacterium , Micrococcus and Sphingobacterium . A complete enzymatic characterization revealed widespread – albeit moderate – cellulase properties in all but one isolate and high xylanase activity in the four CPB isolates. Different enzymatic patterns in terms of opt…

Paving the way for synthetic biology-based bioremediation in Europe

Synthetic biology (SB) has a dual definition. It is both the design and construction of new biological parts, devices and systems, and also the re‐design of existing, natural systems for useful purposes. The latter field is maybe one of the major challenges within this discipline, since the promising prospect that biological systems may be used as biomachines will certainly be exploited in the near future. Synthetic biology has challenging conceptual possibilities (Moya et al., 2009a) and impressive progress has already been made in biotechnology following SB approaches (de Lorenzo and Danchin, 2008). Much more is expected in the near future from current efforts aiming to make synthetic gen…

Fusta de Nobel

L'article descriu la jerarquia en la recerca, i el fet que els mèrits recauen sempre en aquells que es troben a dalt de la piràmide

Hymenopteran specificity of Bacillus thuringiensis strain PS86Q3

Abstract The biological activity of Bacillus thuringiensis (Bt) strain PS86Q3 against five Hymenopteran species was determined by means of bioassays adapted to each species. Four species of sawfly that are important pests of conifers (Diprion pini, Gilpinia hercyniae and Pristiphora abietina) or ornamental plants (Arge rosae), as well as the non-target honeybee, Apis mellifera, were studied. Two out of the four sawfly species tested were found to be sensitive to PS86Q3 crystals or spore/crystal suspensions. A sporulated culture of this strain was moderately active on D. pini, and a complete bioassay with solubilized crystals was performed to estimate the LC50 of 4.9 mg/ml. Pristiphora abiet…

MOESM6 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 6: Table S6. Number of sequences and mean length for bacteria from the acidification stages.

Designing de novo: interdisciplinary debates in synthetic biology

Synthetic biology is often presented as a promissory field that ambitions to produce novelty by design. The ultimate promise is the production of living systems that will perform new and desired functions in predictable ways. Nevertheless, realizing promises of novelty has not proven to be a straightforward endeavour. This paper provides an overview of, and explores the existing debates on, the possibility of designing living systems de novo as they appear in interdisciplinary talks between engineering and biological views within the field of synthetic biology. To broaden such interdisciplinary debates, we include the views from the social sciences and the humanities and we point to some fu…

Microbial communities of the Mediterranean rocky shore: ecology and biotechnological potential of the sea‐land transition

Microbial communities from harsh environments hold great promise as sources of biotechnologically relevant strains and compounds. In the present work, we have characterized the microorganisms from the supralittoral and splash zone in three different rocky locations of the Western Mediterranean coast, a tough environment characterized by high levels of irradiation and large temperature and salinity fluctuations. We have retrieved a complete view of the ecology and functional aspects of these communities and assessed the biotechnological potential of the cultivable microorganisms. All three locations displayed very similar taxonomic profiles, with the genus Rubrobacter and the families Xenoco…

Complete genome sequence of a new Bacteroidaceae bacterium isolated from anaerobic biomass digestion

Here, we present the genome sequence and annotation of HV4-6-C5C, a bacterial strain isolated from a mesophilic two-stage laboratory-scale leach bed biogas reactor system. Strain HV4-6-C5C may represent a new genus of the family Bacteroidaceae and may have a key role in acidogenesis and acetogenesis steps during anaerobic biomass digestion.

Nature versus design: synthetic biology or how to build a biological non-machine.

The engineering ideal of synthetic biology presupposes that organisms are composed of standard, interchangeable parts with a predictive behaviour. In one word, organisms are literally recognized as machines. Yet living objects are the result of evolutionary processes without any purposiveness, not of a design by external agents. Biological components show massive overlapping and functional degeneracy, standard-free complexity, intrinsic variation and context dependent performances. However, although organisms are not full-fledged machines, synthetic biologists may still be eager for machine-like behaviours from artificially modified biosystems.

Analysis of pteridines in Pyrrhocoris apterus (L.) (Heteroptera, Pyrrhocoridae) during development and in body-color mutants

By using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), five different pteridines have been quantified in extracts from Pyrrhocoris apterus: neopterin, isoxanthopterin, isoxantholumazine (violapterin), 7-methylxanthopterin, and erythropterin. Biopterin was also detected using HPLC. Pteridines have been analyzed separately in bodies and eyes of the wild type regarding developmental stage and sex. The pteridine content in both bodies and eyes increased from nymphs to 2-day-old adults. After this period, the concentration of pteridines in the eyes of adults remained approximately constant, while in the bodies isoxantholumazine, 7-methylxanthopterin, and isox…

A simple DNA extraction method suitable for PCR detection of genetically modified maize.

BACKGROUND: The polymerase chain reaction (PCR) is a powerful tool that is being increasingly used for detection of transgenic DNA. PCR requires only a minute quantity of template, but sensitive and accurate testing requires DNA of sufficient purity and free from inhibitors such as plant polysaccharides. Several standard protocols are available for this purpose, but they usually involve several steps, imply destruction of the maize kernel, or are time-consuming. Our aim was to develop a fast and simple extraction method to isolate a raw DNA-containing solution from maize tissues suitable for use as a template in a PCR-based detection assay with specific oligonucleotides directed to the iden…

Can life be standardized? Current challenges in biological standardization

The concept of standard strongly evokes machines, industries, electric or mechanical devices, vehicles, or furniture. Indeed, our technological civilization would not be possible – at least in the terms it is structured today – without universal, reliable components, whose acknowledged use results in competitive costs, robustness and interchangeability. For example, an Ikea screw can be used in a wide set of structurally dissimilar furniture and an app can be run on many different smartphones. The very concept of standardization is linked to the industrial revolution and mass production of goods through assembly lines. The question we will try to answer in the present paper is the extent to…

From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Background Separating acidification and methanogenic steps in anaerobic digestion processes can help to optimize the process and contribute to producing valuable sub-products such as methane, hydrogen and organic acids. However, the full potential of this technology has not been fully explored yet. To assess the underlying fermentation process in more detail, a combination of high-throughput sequencing and proteomics on the acidification step of plant material (grass) at both mesophilic and thermophilic temperatures (37 and 55 °C, respectively) was applied for the first time. Results High-strength liquor from acidified grass biomass exhibited a low biodiversity, which differed greatly depen…

Yeast cultures with UCP1 uncoupling activity as a heating device

7 páginas, 5 figuras, 3 tablas -- PAGS nros. 300-306

Bioprospecting the solar panel microbiome: High-throughput screening for antioxidant bacteria in a caenorhabditis elegansModel

Microbial communities that are exposed to sunlight typically share a series of adaptations to deal with the radiation they are exposed to, including efficient DNA repair systems, pigment production and protection against oxidative stress, which makes these environments good candidates for the search of novel antioxidant microorganisms. In this research project, we isolated potential antioxidant pigmented bacteria from a dry and highly-irradiated extreme environment: solar panels. High-throughput in vivo assays using Caenorhabditis elegans as an experimental model demonstrated the high antioxidant and ultraviolet-protection properties of these bacterial isolates that proved to be rich in car…

MOESM4 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 2: Table S4. Mascot results.

MOESM5 of From grass to gas: microbiome dynamics of grass biomass acidification under mesophilic and thermophilic temperatures

Additional file 3: Table S5. Differentially expressed proteins.

Un microorganisme per a cada ocasió

Els qui treballem en microbiologia no podem queixar-nos de ser particularment incompresos pel públic en general: a diferència del bosó de Higgs, la teoria de les cordes o la prima de risc, tothom té una idea relativament acurada de què és un bacteri. Per si de cas, donem algunes dades sobre els microorganismes: són formes de vida unicel·lulars; amb tota probabilitat les primeres formes de vida a aparèixer sobre el nostre planeta; són molt menuts (l’espessor d’una ungla i un bacteri són, proporcionalment, com el Grand Canyon i un humà) i hi són pertot arreu. Hi ha espores fúngiques i bacteris a l’aire, a l’aigua, al sòl i damunt tots els éssers vius. Estem literalment coberts per bacteris, d…