The commonly used Staphylococcus aureus laboratory strain 8325-4 bears a naturally occurring mutation in the sigB gene, which encodes the σB transcription factor. This mutation affects the regulation of various virulence factors, including the production of extracellular proteases. The σB regulon is a complex network of genes that are regulated by σB, and its dysregulation has been implicated in the pathogenesis of S. aureus. Understanding the role of σB in the regulation of virulence factors is crucial for the development of effective therapeutic strategies against S. aureus infections. This study aims to investigate the role of σB in the regulation of extracellular proteases in S. aureus and to identify potential targets for the development of novel antimicrobial agents.