Project description:To study the roles of NWMN_0641, we used microarray to compare the transcriptome of the NWMN_0641 deletion strain with that of the wild-type Staphylococcus aureus Newman strain. Transcriptome of the NWMN_0641 deletion mutant strain and the wild-type Newman strain
Project description:The SaeRS two-component regulatory system of Staphylococcus aureus is known to affect the expression of many genes. The SaeS protein is the histidine kinase responsible for phosphorylation of the response regulator SaeR. In S. aureus Newman, the sae system is constitutively expressed due to a point mutation in saeS, relative to other S. aureus strains, which results in substitution of proline for leucine at amino acid 18. Strain Newman is unable to form a robust biofilm and we report here that the biofilm-deficient phenotype is due to the saeSP allele. Replacement of the Newman saeSP with saeSL, or deletion of saeRS, resulted in a biofilm-proficient phenotype. Newman culture supernatants were observed to inhibit biofilm formation by other S. aureus strains, but did not affect biofilm formation by S. epidermidis. Culture supernatants of Newman saeSL or Newman ΔsaeRS had no significant effect on biofilm formation. The inhibitory factor was inactivated by incubation with proteinase K, but survived heating, indicating that the inhibitory protein is heat-stable. The inhibitory protein was found to affect the attachment step in biofilm formation, but had no effect on preformed biofilms. Replacement of saeSL with saeSP in the biofilm-proficient S. aureus USA300 FPR3757 resulted in the loss of biofilm formation. Culture supernatants of USA300 FPR3757 saeSP, did not inhibit biofilm formation by other staphylococci, suggesting that the inhibitory factor is produced but not secreted in the mutant strain. A number of biochemical methods were utilized to isolate the inhibitory protein. Although a number of candidate proteins were identified, none were found to be the actual inhibitor. In an effort to reduce the number of potential inhibitory genes, RNA-Seq analyses were done with wild-type strain Newman and the saeSL and ΔsaeRS mutants. RNA-Seq results indicated that sae regulates many genes that may affect biofilm formation by Newman.
Project description:To study the roles of NWMN_0641, we used microarray to compare the transcriptome of the NWMN_0641 deletion strain with that of the wild-type Staphylococcus aureus Newman strain. Transcriptome of the NWMN_0641 deletion mutant strain and the wild-type Newman strain We sought to obtain the transcriptomes of the NWMN_0641 deletion mutant strain and the wild-type Newman strain when bacteria were grown TSB medium (without glucose)
Project description:Array analysis of total RNA from broncho-alveolar lavage (BAL) from mice infected with influenza virus (PR8) and/or Staphylococcus aureus (Newman)
Project description:We reported the RNA-Seq results of Staphylococcus aureus Newman wild-type, walKD119A, walKV149A and DHBP-treated wild-type strains. We found that mutations of the potential signal transduction residues of WalK attenuate the activity of walKR two-component system, whereas DHBP supplementation activates this two-component system.