Project description:In the transition from recto-vaginal colonizing organism to invasive pathogen, Streptococcus agalactiae (Group B Streptococcus, GBS) must adapt to changes in host temperature, including elevated temperatures due to host fever. To identify genes important to the survival of GBS in response to heat stress, transcriptional profiling was performed using DNA microarray analysis, comparing GBS grown at normal temperature (37˚C) to GBS exposed to elevated temperature (42˚C).
Project description:Regulation of gene expression in response to variable and often adverse environmental conditions is an essential component of microbial pathogenesis. We identified the two-component regulatory system CiaRH in a screen for genes essential for the survival of Streptococcus agalactiae (Group B Streptococcus, GBS) on exposure to in vitro models of environmental stress. We constructed site-directed, non-polar deletion mutations in the regulator gene ciaR and compared the growth of CiaR mutant GBS to wild-type GBS under stressed conditions. CiaR mutant GBS are more sensitive than wild-type GBS to elevated temperature, low pH, chemical mutagens and ultraviolet light; the mutants are also more sensitive to cell-wall active antibiotics and antimicrobial peptides. CiaR mutant strains are markedly attenuated in a mouse model of GBS sepsis. To determine the genes regulated by CiaR that account for these defects, transcriptional profiling was performed using DNA microarray analysis, comparing wild-type GBS to CiaR mutant GBS under non-stressed conditions.
Project description:Transcriptome analysis of Streptococcus agalactiae (group B Streptococcus) grown under control conditions or coincubated with serine hydroxamate to induce the bacterial stringent response
Project description:Streptococcus agalactiae (Lancefield’s group B Streptococcus, GBS) is a major bacterial species of genus Streptococcus and has medical and veterinary importance by affecting mainly humans (Maione et al., 2005; Johri et al., 2006), cattle (Keefe, 1997) and fish (Mian et al., 2009). The GBS is the most important pathogen for the Nile tilapia, a global commodity of the aquaculture sector, causing outbreaks of septicemia and meningoencephalitis (Hernández et al., 2009; Mian et al., 2009).
Project description:Total RNA was isolated from mid-log phase Streptococcus agalactiae cells deficient in SczA (∆sczA strain GU2791), grown in Todd-Hewitt broth (THB) medium and sequenced using Illumina NextSeq500.
Project description:Total RNA was isolated from mid-log phase Streptococcus agalactiae cells deficient in CovR (∆covR strain GU2400), grown in Todd-Hewitt broth (THB) medium and sequenced using Illumina NextSeq500
Project description:Total RNA was isolated from mid-log phase Streptococcus agalactiae cells deficient in CopY (∆copY strain GU2857), grown in Todd-Hewitt broth (THB) medium and sequenced using Illumina NextSeq500.
Project description:Total RNA was isolated from mid-log phase Streptococcus agalactiae 874391 wild-type cells grown in Todd-Hewitt broth (THB) medium and sequenced using Illumina NextSeq500
Project description:Streptococcus agalactiae (Lancefield’s group B Streptococcus, GBS) is a major bacterial species of genus Streptococcus and has medical and veterinary importance by affecting mainly humans (Maione et al., 2005; Johri et al., 2006), cattle (Keefe, 1997) and fish (Mian et al., 2009). The GBS is the most important pathogen for the Nile tilapia, a global commodity of the aquaculture sector, causing outbreaks of septicemia and meningoencephalitis (Hernández et al., 2009; Mian et al., 2009). This study aimed to evaluate the global abundancy of proteins among the main genotypes of GBS isolated from fish identified in Brazil using a label free shotgun liquid chromatography-ultra definition mass spectrometry (LC-UDMSE) approach and to compare the differential expression of proteins identified between isolates from fish and human.
Project description:Total RNA was isolated from mid-log phase Streptococcus agalactiae cells deficient in CopY (∆copY strain GU2857), grown in Todd-Hewitt broth (THB) medium supplemented with 0.25 mM Zn and sequenced using Illumina NextSeq500.
