Project description:To further explore potential molecular mechanisms and pathways by which the presence or absence of the pGKT2 plasmid may be affecting the overall fitness cost in the native Gordonia sp KTR9 strain, transcriptome studies were performed. Transcriptome experiments comparing KTR9 wild-type and mutant strains grown in rich media confirmed the loss of the pGKT2 plasmid and also indicated the loss of the 90 kb pGKT1 plasmid.
Project description:To further explore potential molecular mechanisms and pathways by which the presence or absence of the pGKT2 plasmid may be affecting the overall fitness cost in a transconjugant Rhodococcus jostii RHA1 strain, transcriptome studies were performed. Transcriptome experiments comparing RHA1 wild-type and RHA1 transconjugant strains grown in rich media confirmed the presence of the pGKT2 plasmid.
Project description:This study performed transcriptome sequencing of two newly identified Mycobacterium species, Mycobacterium camsae and Mycobacterium pumcae, under standard culture conditions to establish baseline gene expression profiles. RNA was extracted from cells grown to mid-log phase in standard medium and sequenced using Illumina paired-end technology. The data provide a foundational resource for future functional studies of these novel strains.
Project description:The ESX-5 system from Mycobacterium xenopi was expressed in Mycobacterium smegmatis on a constituatively expressed plasmid. This expression plasmid, pMX-Mxen-ESX-5 enocodes the seceretion complex and 3 secreted substrate pairs : EsxM+EsxN; PE19.1+PPE26.1 ; and PE19.2+PPE26.2. Several mutants in the secretion apparatus were generated and the secretion of the plasmid encoded substrates monitored.
Project description:Test whether it is possible to conjugate a whole plasmid library into a recipient strain without loss of fidelity (as judged by aCGH analysis)
Project description:<p>Gut environments harbour dense microbial ecosystems in which plasmids are widely distributed. Plasmids facilitate the exchange of genetic material among microorganisms while enabling the transfer of a diverse array of accessory functions. However, their precise impact on microbial community composition and function remains largely unexplored. Here we identify a prevalent bacterial toxin and a plasmid-encoded resistance mechanism that mediates the interaction between Lactobacilli and Enterococci. This plasmid is widespread across ecosystems, including the rumen and human gut microbiota. Biochemical characterization of the plasmid revealed a defence mechanism against reuterin, a toxin produced by various gut microbes, such as Limosilactobacillus reuteri. Using a targeted metabolomic approach, we find reuterin to be prevalent across rumen ecosystems with impacts on microbial community structure. Enterococcus strains carrying the protective plasmid were isolated and their interactions with L. reuteri, the toxin producer, were studied in vitro. Interestingly, we found that by conferring resistance against reuterin, the plasmid mediates metabolic exchange between the defending and the attacking microbial species, resulting in a beneficial relationship or mutualism. Hence, we reveal here an ecological role for a plasmid-coded defence system in mediating a beneficial interaction. </p>