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Published on: January 3, 2020
Inhibition of colony-spreading activity of Staphylococcus aureus by secretion of δ-hemolysin
Yosuke Omae1, Kazuhisa Sekimizu, Chikara Kaito
1Laboratory of Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, 3-1, 7-Chome, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Abstract:
Staphylococcus aureus spreads on the surface of soft agar, a phenomenon we termed "colony spreading." Here, we found that S. aureus culture supernatant inhibited colony spreading. We purified δ-hemolysin (Hld, δ-toxin), a major protein secreted from S. aureus, as a compound that inhibits colony spreading. The culture supernatants of hld-disrupted mutants had 30-fold lower colony-spreading inhibitory activity than those of the parent strain. Furthermore, hld-disrupted mutants had higher colony-spreading ability than the parent strain. These results suggest that S. aureus negatively regulates colony spreading by secreting δ-hemolysin.
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