Unknown,Transcriptomics,Genomics,Proteomics

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Roles of relSpn in Stringent Response, Global Regulation, and Virulence of Serotype 2 Streptococcus pneumoniae D39

ABSTRACT: Transcriptome analysis of D39 rel+Spn and delta-relSpn strains treated with mupirocin revealed relSpn-independent (translation stress), relSpn-dependent (stringent response), and delta-relSpn-dependent changes suggesting that relSpn and (p)ppGpp amount play wide-ranging homeostatic roles in pneumococcal physiology, besides adjusting macromolecular synthesis and transport in response to nutrient availability. Wildtype and rel deletion mutant (Delta rel) bacteria were grown statically in BHI broth at 37C in an atmosphere of 5% CO2. Cultures were divided in two upon reaching a density of OD620 ~0.1, and lithium mupirocin was added to one culture (t=0) to a final concentration of 100 ng per mL. Treated and untreated cultures were harvested after 20 min further incubation and RNA was extracted by a hot lysis-acid phenol protocol. We performed the following comparisons: Wildtype + mupirocin versus Wildtype untreated (reference); Delta rel + mupirocin versus Delta rel untreated (reference); Delta rel untreated versus Wildtype untreated (reference); Delta rel + mupirocin versus Wildtype + mupirocin (reference). For each comparison, microarray data were obtained from three independent biological replicates and included one dye swap.

ORGANISM(S): Streptococcus pneumoniae

SUBMITTER: Kyle Wayne

PROVIDER: E-GEOD-14750 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Roles of relSpn in Stringent Response, Global Regulation, and Virulence of Serotype 2 Streptococcus pneumoniae D39

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