Search results for "Prophages"
showing 5 items of 5 documents
Mobile genetic element proliferation and gene inactivation impact over the genome structure and metabolic capabilities of Sodalis glossinidius, the s…
2010
Abstract Background Genome reduction is a common evolutionary process in symbiotic and pathogenic bacteria. This process has been extensively characterized in bacterial endosymbionts of insects, where primary mutualistic bacteria represent the most extreme cases of genome reduction consequence of a massive process of gene inactivation and loss during their evolution from free-living ancestors. Sodalis glossinidius, the secondary endosymbiont of tsetse flies, contains one of the few complete genomes of bacteria at the very beginning of the symbiotic association, allowing to evaluate the relative impact of mobile genetic element proliferation and gene inactivation over the structure and funct…
Identification of Gip as a novel phage‐encoded gyrase inhibitor protein of Corynebacterium glutamicum
2021
By targeting key regulatory hubs of their host, bacteriophages represent a powerful source for the identification of novel antimicrobial proteins. Here, a screening of small cytoplasmic proteins encoded by the CGP3 prophage of Corynebacterium glutamicum resulted in the identification of the gyrase-inhibiting protein Cg1978, termed Gip. Pull-down assays and surface plasmon resonance revealed a direct interaction of Gip with the gyrase subunit A (GyrA). The inhibitory activity of Gip was shown to be specific to the DNA gyrase of its bacterial host C. glutamicum. Overproduction of Gip in C. glutamicum resulted in a severe growth defect as well as an induction of the SOS response. Furthermore, …
Biogenesis and roles of Lacticaseibacillus casei BL23 membrane vesicles
2023
Gram-positive bacteria of the species Lacticaseibacillus casei (formerly known as Lactobacillus casei) are fermentative bacilli found in dairy products that are known for their anti-inflammatory properties and beneficial effects against pathogens. Like all living organisms, L. casei produces nanostructures of 20 to 400 nm in diameter bounded by a lipid membrane called membrane vesicles (MVs). MVs have been shown to contain various cellular constituents and exert multiple functions. However, despite the growing interest in Gram-positive MVs over the past 10 years, the mechanisms of biogenesis and the roles played by these vesicles remain poorly characterized. In this context, the objectives …
Isolation in small populations of Wayampi Amerindians promotes endemicity and homogenisation of their faecal virome, but its distribution is not enti…
2018
The isolated community of the Wayampi Amerindians has been extensively studied for the presence of beta lactamase-producing enterobacteria and their gut microbiota. However, no information about their virome was available. This study tries to establish potential associations between the virome and diverse epidemiological data, through the metagenomic study of the faecal prophages and DNA viruses from 31 samples collected in 2010. Taxonomic assignments, composition, abundance and diversity analyses were obtained to characterise the virome and were compared between groups according to several demographic, environmental and medical data. Prophages outnumbered viruses. Composition and abundance…
The effect of a temperature-sensitive prophage on the evolution of virulence in an opportunistic bacterial pathogen.
2022
https://doi.org/10.1111/mec.16638 Abstract Viruses are key actors of ecosystems and have major impacts on global biogeochemical cycles. Prophages deserve particular attention as they are ubiquitous in bacterial genomes and can enter a lytic cycle when triggered by environmental conditions. We explored how temperature affects the interactions between prophages and other biological levels by using an opportunistic pathogen, the bacterium Serratia marcescens, that harbours several prophages and that had undergone an evolution experiment under several temperature regimes. We found that the release of one of the prophages was temperature-sensitive and malleable to evolutionary changes. We furthe…