Renata Matos - Academia.edu (original) (raw)

Papers by Renata Matos

The AI-2 i nterspecies quorum-sensing molecule is produced by the LuxS enzyme and has been ascrib... more The AI-2 i nterspecies quorum-sensing molecule is produced by the LuxS enzyme and has been ascribed a role in virulence in several bacteria. The nosocomial pathogen Enterococcus faecalis inhabits several different environments where multispecies communities are established. However, despite the presence of a luxS gene in this pathogen, its role in E. faecalis pathogenesis has never been assessed. In the present work, we deleted the luxS gene from the vancomycin-resistant clinical isolate E. faecalis V583 and demonstrated the lack of AI-2 production by the mutant strain. Using microarrays and externally added (S)-4,5-dihydroxy-2,3-pentanedione we showed that AI-2 is not sensed by E. faecalis as a canonical quorum-sensing molecule and that the luxS mutation caused pleiotropic effects in gene expression, which could not be complemented by extracellularly added AI-2. These global differences in gene expression affected several gene functional roles, mainly those enrolled in metabolism a...

mSphere, 2019

E. faecalis strain VE14089 was derived from V583 cured of its plasmids. Although VE14089 had no m... more E. faecalis strain VE14089 was derived from V583 cured of its plasmids. Although VE14089 had no major DNA rearrangements, it presented significant growth and host adaptation differences from the reference strain V583 of our collection. To construct a strain with better fitness, we sequenced the genome of VE14089, identified single nucleotide polymorphisms (SNPs), and repaired the genes that could account for these changes. Using this reference-derivative strain, we provide a novel genetic system to understand the role of the variable region of epa in the enterococcal lifestyle.

RNA Biology, 2015

We discovered a chromosomal locus containing 2 toxin-antitoxin modules (TAs) with an antisense tr... more We discovered a chromosomal locus containing 2 toxin-antitoxin modules (TAs) with an antisense transcriptional organization in the E. faecalis clinical isolate V583. These TAs are homologous to the type I txpA-ratA system and the type II mazEF, respectively. We have shown that the putative MazF is toxic for E. coli and triggers RNA degradation, and its cognate antitoxin MazE counteracts toxicity. The second module, adjacent to mazEF, expresses a toxin predicted to belong to the TxpA type I family found in Firmicutes, and the antisense RNA antidote, RatA. Genomic analysis indicates that the cis-association of mazEF and txpA-ratA modules has been favored during evolution, suggesting a selective advantage for this TA organization in the E. faecalis species. We showed regulatory interplays between the 2 modules, involving transcription control and RNA stability. Remarkably, our data reveal that MazE and MazEF have a dual transcriptional activity: they act as autorepressors and activate ratA transcription, most likely in a direct manner. RatA controls txpA RNA levels through stability. Our data suggest a pivotal role of MazEF in the coordinated expression of mazEF and txpA-ratA modules in V583. To our knowledge, this is the first report describing a crosstalk between type I and II TAs.

International Journal of Food Microbiology, 2012

Enterococcus faecalis is a nosocomial opportunistic pathogen, but is also found in fermented food... more Enterococcus faecalis is a nosocomial opportunistic pathogen, but is also found in fermented food products where it plays a fundamental role in the fermentation process. Previously, we have described the nonstarter E. faecalis cheese isolate QA29b as harboring virulence genes and proven to be virulent in Galleria mellonella virulence model. In this study, we further characterized this food strain concerning traits relevant for the host-pathogen relationship. QA29b was found to belong to sequence type (ST) 72, a common ST among food isolates, and thus we consider it as a good representative of food E. faecalis strains. It demonstrated high ability to form biofilms, to adhere to epithelial cells and was readily eliminated by J774.A1 macrophage cells. Despite carrying the cps locus associated with the capsular polysaccharide CPS 2 type, cps genes were not expressed, likely due to an IS6770 inserted in the cpsC-cpsK promoter region. This work constitutes the first study of traits important for interaction, colonization and infection in the host performed on a good representative of E. faecalis food isolates. Reported results stress the need for a reliable serotyping assay of E. faecalis, as cps genotyping may not be reliable. Overall, QA29b characterization shows that despite its virulence potential in an insect model, this food strain is readily eliminated by mammalian macrophages. Thus, fine tuned approaches combining cellular and mammalian models are needed to address and elucidate the multifactorial aspect of virulence potential associated with food isolates.

International Journal of Antimicrobial Agents, 2009

Study on the dissemination of the bcrABDR cluster in Enterococcus spp. reveals that the BcrAB tra... more Study on the dissemination of the bcrABDR cluster in Enterococcus spp. reveals that the BcrAB transporter is sufficient to confer highlevel bacitracin resistance

The AI-2 i nterspecies quorum-sensing molecule is produced by the LuxS enzyme and has been ascrib... more The AI-2 i nterspecies quorum-sensing molecule is produced by the LuxS enzyme and has been ascribed a role in virulence in several bacteria. The nosocomial pathogen Enterococcus faecalis inhabits several different environments where multispecies communities are established. However, despite the presence of a luxS gene in this pathogen, its role in E. faecalis pathogenesis has never been assessed. In the present work, we deleted the luxS gene from the vancomycin-resistant clinical isolate E. faecalis V583 and demonstrated the lack of AI-2 production by the mutant strain. Using microarrays and externally added (S)-4,5-dihydroxy-2,3-pentanedione we showed that AI-2 is not sensed by E. faecalis as a canonical quorum-sensing molecule and that the luxS mutation caused pleiotropic effects in gene expression, which could not be complemented by extracellularly added AI-2. These global differences in gene expression affected several gene functional roles, mainly those enrolled in metabolism a...

mSphere, 2019

E. faecalis strain VE14089 was derived from V583 cured of its plasmids. Although VE14089 had no m... more E. faecalis strain VE14089 was derived from V583 cured of its plasmids. Although VE14089 had no major DNA rearrangements, it presented significant growth and host adaptation differences from the reference strain V583 of our collection. To construct a strain with better fitness, we sequenced the genome of VE14089, identified single nucleotide polymorphisms (SNPs), and repaired the genes that could account for these changes. Using this reference-derivative strain, we provide a novel genetic system to understand the role of the variable region of epa in the enterococcal lifestyle.

RNA Biology, 2015

We discovered a chromosomal locus containing 2 toxin-antitoxin modules (TAs) with an antisense tr... more We discovered a chromosomal locus containing 2 toxin-antitoxin modules (TAs) with an antisense transcriptional organization in the E. faecalis clinical isolate V583. These TAs are homologous to the type I txpA-ratA system and the type II mazEF, respectively. We have shown that the putative MazF is toxic for E. coli and triggers RNA degradation, and its cognate antitoxin MazE counteracts toxicity. The second module, adjacent to mazEF, expresses a toxin predicted to belong to the TxpA type I family found in Firmicutes, and the antisense RNA antidote, RatA. Genomic analysis indicates that the cis-association of mazEF and txpA-ratA modules has been favored during evolution, suggesting a selective advantage for this TA organization in the E. faecalis species. We showed regulatory interplays between the 2 modules, involving transcription control and RNA stability. Remarkably, our data reveal that MazE and MazEF have a dual transcriptional activity: they act as autorepressors and activate ratA transcription, most likely in a direct manner. RatA controls txpA RNA levels through stability. Our data suggest a pivotal role of MazEF in the coordinated expression of mazEF and txpA-ratA modules in V583. To our knowledge, this is the first report describing a crosstalk between type I and II TAs.

International Journal of Food Microbiology, 2012

Enterococcus faecalis is a nosocomial opportunistic pathogen, but is also found in fermented food... more Enterococcus faecalis is a nosocomial opportunistic pathogen, but is also found in fermented food products where it plays a fundamental role in the fermentation process. Previously, we have described the nonstarter E. faecalis cheese isolate QA29b as harboring virulence genes and proven to be virulent in Galleria mellonella virulence model. In this study, we further characterized this food strain concerning traits relevant for the host-pathogen relationship. QA29b was found to belong to sequence type (ST) 72, a common ST among food isolates, and thus we consider it as a good representative of food E. faecalis strains. It demonstrated high ability to form biofilms, to adhere to epithelial cells and was readily eliminated by J774.A1 macrophage cells. Despite carrying the cps locus associated with the capsular polysaccharide CPS 2 type, cps genes were not expressed, likely due to an IS6770 inserted in the cpsC-cpsK promoter region. This work constitutes the first study of traits important for interaction, colonization and infection in the host performed on a good representative of E. faecalis food isolates. Reported results stress the need for a reliable serotyping assay of E. faecalis, as cps genotyping may not be reliable. Overall, QA29b characterization shows that despite its virulence potential in an insect model, this food strain is readily eliminated by mammalian macrophages. Thus, fine tuned approaches combining cellular and mammalian models are needed to address and elucidate the multifactorial aspect of virulence potential associated with food isolates.

International Journal of Antimicrobial Agents, 2009

Study on the dissemination of the bcrABDR cluster in Enterococcus spp. reveals that the BcrAB tra... more Study on the dissemination of the bcrABDR cluster in Enterococcus spp. reveals that the BcrAB transporter is sufficient to confer highlevel bacitracin resistance