Bacterial hemolysins are exotoxins that attack blood cell membranes and cause cell rupture. Beta-hemolysin is a phospholipase C with specific activity toward sphingomyelins. Has a high specificity for sphingomyelin, hydrolyzes lysophosphatidylcholine at a much lower rate, but has no activity towards phosphatidylcholine, phosphatidylethanolamine, or phosphatidylserine 