Search results for "Microbio"
showing 10 items of 8741 documents
Land use effects on bacterial diversity in Mediterranean soils vulnerable to desertification
2021
The soil microbiota is recognized as key player in both diversity and productivity of terrestrial ecosystems and it is mandatory to include its role in soil quality evaluation. The bacterial communities in soils vulnerable to desertification can undergo perturbations by various human activities, such as unsustainable land use and management, and by climate change. Alteration in microbial diversity and composition are sentinels of the impact of environmental changes on soil quality. Within the LIFE Desert-Adapt project we analyze the soil bacterial diversity and composition across European Soils threatened by desertification in the southern Mediterranean regions (Italy, Spain and Portugal) a…
Discovery of a new class of sortase a transpeptidase inhibitors to tackle gram-positive pathogens: 2-(2-phenylhydrazinylidene)alkanoic acids and rela…
2016
A FRET-based random screening assay was used to generate hit compounds as sortase A inhibitors that allowed us to identify ethyl 3-oxo-2-(2-phenylhydrazinylidene)butanoate as an example of a new class of sortase A inhibitors. Other analogues were generated by changing the ethoxycarbonyl function for a carboxy, cyano or amide group, or introducing substituents in the phenyl ring of the ester and acid derivatives. The most active derivative found was 3-oxo-2-(2-(3,4dichlorophenyl)hydrazinylidene)butanoic acid (2b), showing an IC50 value of 50 µM. For a preliminary assessment of their antivirulence properties the new derivatives were tested for their antibiofilm activity. The most active compo…
LACTOBACILLI IN SOURDOUGH FERMENTATION: A REVIEW
2007
Sourdough technology is widely used; it is employed in bread making and for the production of cakes. Sourdough is characterized by a complex microbial ecosystem, mainly represented by lactic acid bacteria and yeasts, whose fermentation confers to the resulting bread its characteristic features such as palatability and high sensory quality. Investigation of the microbial composition of sourdough is relevant in order to determine the potential activities of sourdough microorganisms. This review focuses on the role of the most important group of sourdough fermenting bacteria that consists of lactobacilli; species that belong to the Lactobacillus genus are the main responsible of flavor develop…
Preliminary Investigation of Biogenic Amines in Type I Sourdoughs Produced at Home and Bakery Level
2022
During a survey for isolating sourdough lactic acid bacteria (LAB), 20 dough samples produced at the bakery level (BL) or home-made (HM) were collected. An enzyme-based colorimetric method revealed a total biogenic amines (BAs) concentration in the range 41.4–251.8 ppm for six (three BL and three HM) sourdoughs characterised by unpleasant odours. Eight BAs generally investigated in foods were identified and quantified from these six samples by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). Only one HM sample contained almost all analysed BAs. Tryptamine was exclusively detected in HM sourdoughs (0.71–24.1 ppm). Putrescine, tryptamine, …
Microbial resources and sparkling wine differentiation : state of the arts
2022
Consumers’ increasing interest in sparkling wine has enhanced the global market’s demand. The pro-technological yeasts strains selected for the formulation of microbial starter cultures are a fundamental parameter for exalting the quality and safety of the final product. Nowadays, the management of the employed microbial resource is highly requested by stakeholders, because of the increasing economic importance of this oenological sector. Here, we report an overview of the production processes of sparkling wine and the main characterisation criteria to select Saccharomyces and non-Saccharomyces strains appropriate for the preparation of commercial starter cultures dedicated to the primary a…
Overexpression of SAMDC1 gene in Arabidopsis thaliana increases expression of defense-related genes as well as resistance to Pseudomonas syringae and…
2014
It has been previously described that elevation of endogenous spermine levels in Arabidopsis could be achieved by transgenic overexpression of S-Adenosylmethionine decarboxylase (SAMDC) or Spermine synthase (SPMS). In both cases, spermine accumulation had an impact on the plant transcriptome, with up-regulation of a set of genes enriched in functional categories involved in defense-related processes against both biotic and abiotic stresses. In this work, the response of SAMDC1-overexpressing plants against bacterial and oomycete pathogens has been tested. The expression of several pathogen defense-related genes was induced in these plants as well as in wild type plants exposed to an exogeno…
Genetic manipulation of spiramycin-producing strain Streptomyces ambofaciens ATCC 23877 by φC31 Att/Int system-based vectors results in a significant…
The genus Streptomyces produces about two-thirds of naturally occurring antibiotics and many other biologically active secondary metabolites. The genetic manipulation of Streptomycetes is often labor and time intensive due to their large genome and complex development. Much progress has been made to develop gene transfer methods useful to construct antibiotic-producing strains with improved properties. The φC31 Att/Int system is an integration system that has been widely used to produce stable recombinants in Actinomycetes and its integration site is an attB site located in a pirin-like gene (pirA) of the bacterial chromosome. In this study we demonstrate that the integration of φC31 DNA in…
Bacterial biofilms: a challenge in the discovery of new anti-infective agents.
2010
The ability to form a biofilm, bacterial communities able to grow on surfaces and surrounded by an extracellular polymeric substance biofilm agents.Our research group focused on discovering of novel chemical agents of potential therapeutic utility in the treatment of staphylococcal biofilm-associatedinfections by screening novel compounds (synthetic or natural). In a recent study, the antistaphylococcalbiofilm activity of pyrrolomycins C,D, F1, F2a, F2b, F3 a family of halogenated pyrroles which are naturally produced byActinosporangium vitaminophylum and of the synthesized related compounds I, II, III were investigated and compared (Schillaci et al, 2010). We also focused on marine inverte…
Understanding the microbial biogeography of ancient human dentitions to guide study design and interpretation
2021
AbstractThe oral cavity is a heterogeneous environment, varying in factors such as pH, oxygen levels, and salivary flow. These factors affect the microbial community composition and distribution of species in dental plaque, but it is not known how well these patterns are reflected in archaeological dental calculus. In most archaeological studies, a single sample of dental calculus is studied per individual and is assumed to represent the entire oral cavity. However, it is not known if this sampling strategy introduces biases into studies of the ancient oral microbiome. Here, we present the results of a shotgun metagenomic study of a dense sampling of dental calculus from four Chalcolithic i…