Transposon sequencing during experimental osteomyelitis reveals hypoxic responses as key components of the staphylococcal-host interaction

The Staphylococcus aureus two-component regulatory system, SrrAB, coordinates hypoxic responses during in vitro growth conditions. S. aureus Affymetrix GeneChips were used to compare S. aureus expression properties of wild type and isogenic ssrA mutant cells during aerobic growth conditions. S. aureus Affymetrix GeneChips were also used to compare the S. aureus expression properties of wild type and isogenic ssrA mutant cells during hypoxic growth conditions. Few differences were observed between the expression properties of S. aureus wildtype and ssrA mutant cells during aerobic growth. Significant differences were observed between the expression properties of S. aureus wild type and ssrA mutant cells during hypoxic growth. S. aureus strain USA300 (wild type) or an isogenic srrAB mutant (DssrA) were grown in laboratory medium to exponential under aerobic or hypoxic growth conditions, total bacterial RNA was isolated, labeled and applied to Affymetrix GeneChips. We sought to determine whether the transcriptional profiles of S. aureus wild type and ssrAB mutant cells differed during aerobic and hypoxic growth conditions.