Cytolysin gene and gene product

摘要

A Salmonella gene, encoding a cytolysin, has been identified by screening for hemolysis on blood agar. The gene (slyA) is present in every strain of Salmonella examined in Shigella, and enteroinvasive Escherichia coli (EIEC) but not in other enterobacteriaceae. It is encoded near 28.5 minutes on the chromosome. A SlyA (salmolysin) has hemolytic and cytolytic activity and has a molecular weight predicted by the DNA sequence. LD50 and infection kinetics data in mice indicate that the toxin is required for virulence and facilitates Salmonella survival within peritoneal macrophages.