Serotype F double- and triple-converting phage insertionally inactivate the Staphylococcus aureus β-toxin determinant by a common molecular mechanism

Abstract

The precise molecular mechanism of Staphylococcus aureus β-toxin inactivation by the serotype F triple-converting phage φ42, φA1 and φA3 was investigated. Sequence analysis of the φ42 (attP) and Staphylococcus aureus (attB) attachment sites and the left (attL) and right (attR) chromosomal/bacteriophage DNA junctions of individual lysogens, each harbouring a triple-converting phage, revealed the presence of a common 14-bp core sequence in all four sites. These findings indicate that the genomes of the triple-converting phage integrate into the 5′-end of the β-toxin gene (hlb) by a site- and orientation-specific mechanism identical to that previously described for the serotype F double-converting phage φ13. © 1993.