The Properties of Phospholipase Enzymes in Staphylococcal Toxins

Abstract

SUMMARYTwo phospholipase enzymes have been identified in toxic preparations from Staphylococcus aureus, each having a mode of action like that of phospholipase C. One enzyme hydrolysed phosphatidyl inositol and lysophosphatidyl inositol, while the other hydrolysed sphingomyelin and lysophosphatidyl choline. The latter enzyme was always associated with /I-haemolysin activity and it is concluded that P-haemolysin, sphingomyelinase and lysophospholipase are activities of one protein. A phospholipase A was also detected in a toxic preparation from an ap strain.

Exotoxins of Staphylococcus aureus

“…This activity requires the presence of Mg 2ϩ and is limited with specificity for sphingomyelin and lyso-phosphatidylcholine. The differing susceptibility of erythrocytes to betahemolysin may be due to the differing sphingomyelin contents of erythrocytes (49). A mechanism to explain the hot-cold hemolysis was put forward by Low and Freer (103) in 1977.…”

Cereolysin: Production, Purification and Partial Characterization

“…protein (wiseman, 1965). The latter lysin has been shown (Doery, Magnusson, Gulasekharam & Pearson, 1965) to be a phospholipase C with a preference for sphingomyelin and lysophosphatidylcholine. During the present work we have been aware of the possibility that cereolysin might be a similar enzyme, but purified cereolysin produced no turbidity in diluted egg yolk and therefore appears to be completely free from phospholipase C activity.…”

Growth Inhibition, Morphological Change, and Ectoenzyme Release of LLC-PK1 Cells by Phosphatidylinositol-specific Phospholipase C ofBacillus thuringiensis

“…Bacterial phosphatidylinositol-specific phospholipase C (EC 3.1.4.10, monophosphatidylinositol inositolphosphohydrolase, PI-PLC) was first found in toxic preparations from Staphylococcus aureus 1 ) and Bacillus cereus. 2) Ikezawa et al 3 .4) and Low and Finean 5) purified this enzyme from Bacillu,s' sp.…”