Search results for "MICROBIOLOGIA"
showing 10 items of 1027 documents
The small protein TrpM is involved in Streptomyces coelicolor differentiation
Biodegradation of organophosphorus pesticides by soil bacteria.
2009
A number of studies in the 1980s and 1990s showed that crop-protection products, applied to drained fields, could move downwards through the soil profile and to the groundwater. Organophosphorus insecticides (OPs) are used all over the world for crop protection, for other agricultural practices such as sheep dipping and, in aquaculture, for the control of sea lice. Ops besides showing a specific neurotoxicity and have also been related to various modern diseases, including Creutzfeldt–Jakob (CJD) and the Gulf War syndrome. Although OPs are less persistent than Organoclorine pesticides (OCs), they still constitute an environmental risks thus increasing the social concern about their levels i…
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…
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…
Exploring long chain n-alkane metabolism in Gordonia sp. strain SoCg
2011
Effects of arbuscular mycorrhizal symbiosis on nitrogen dynamics in Mediterranean agro-ecosystems
2010
Le simbiosi arbuscolo micorriziche (AM) sono formate dai funghi appartenenti al phylum Glomeromicota e piante superiori. Le simbiosi (AM) sono caratterizzate dalla penetrazione attiva del fungo dentro negli spazi intercellulari della cortaccia radicale e dalla formazione di strutture di scambio (chiamate ‘arbuscoli’) all’interno della parere cellulare. Gli arbuscoli sono strutture ramificate formate dal fungo AM all’interno della cellula vegetale invasa e sono indubbiamente gli organi chiave della simbiosi. Durante la loro formazione, la cellula vegetale si trasforma radicalmente. In particolare, la membrana cellulare si invagina e una membrana periarbuscolare con una ampia superficie di sc…