Quadruple or quintuple conversion of hlb, sak, sea (or sep), scn, and chp genes by bacteriophages in non-β-hemolysin-producing bovine isolates of Staphylococcus aureus

Abstract

In 13 of 43 non-β-hemolysin-producing bovine isolates of Staphylococcus aureus, two truncated β-hemolysin ( hlb) genes were demonstrated by PCR and sequencing, and one truncated hlb gene was located beside the integrase ( int) gene of phage origin. The staphylokinase ( sak) gene was detected in all 13 isolates in which the truncated hlb genes were detected by PCR. Enterotoxin A ( sea) and enterotoxin P ( sep) genes were also detected in 5 and 2 of the 13 isolates, respectively. Moreover, the scn and chp genes encoding staphylococcal complement inhibitor (SCIN) and chemotaxis inhibitory protein of S. aureus (CHIPS) were detected in 13 and 4 of the 13 isolates, respectively. The bacteriophage induced by mitomycin C treatment was able to lysogenize one β-hemolysin-producing isolate of S. aureus, and the sak and scn genes were detected from the lysogenized isolate. These results suggest quadruple or quintuple conversion of hlb, sak, sea (or sep), scn, and chp genes by bacteriophages among non-β-hemolysin-producing bovine isolates of S. aureus.