Purification and characterization of lysophospholipase-transacylase (h-LPTA) from a highly virulent strain of Candida albicans

Biochim Biophys Acta. 1995 Jul 13;1257(2):181-8. doi: 10.1016/0005-2760(95)00072-k.

Abstract

A lysophospholipase-transacylase (h-LPTA) was purified to homogeneity from a clinical isolate of Candida albicans (C. albicans) that had high extracellular phospholipase activity (strain 16240). The purified enzyme was a glycoprotein with molecular mass of 84 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The specific activities of the enzyme were 117 mumol/min per mg protein for fatty acid release and 459 mumol/min per mg protein for phosphatidylcholine (PC) formation. An apparent Km of the hydrolase activity of the enzyme for 1-palmitoyl-sn-glycero-3-phosphocholine (1-palmitoyl-lyso-PC) was 60.6 microM. The enzyme had a pH optimum at 6.0. Transacylase activity of the enzyme was partially inhibited by palmitoylcarnitine (35% inhibition) and N-ethylmaleimide. In contrast, the hydrolase activity of the enzyme was stimulated by palmitoylcarnitine but was partially inhibited by N-ethylmaleimide. The enzyme exhibited broad specificity to lyso-phospholipids. The h-LPTA activity was not dependent on divalent cations (Ca2+ and Mg2+) and was not inhibited by addition of EDTA or EGTA. These results show that C. albicans strain 16240 with high extracellular phospholipase activity produced h-LPTA in large amount. This enzyme is biochemically distinct from the LPTA enzyme previously isolated from C. albicans 3125.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acyltransferases / antagonists & inhibitors
  • Acyltransferases / chemistry
  • Acyltransferases / isolation & purification*
  • Candida albicans / enzymology*
  • Candida albicans / genetics
  • Candidiasis / microbiology
  • Glycoproteins / isolation & purification
  • Kinetics
  • Lysophospholipase / antagonists & inhibitors
  • Lysophospholipase / chemistry
  • Lysophospholipase / isolation & purification*
  • Molecular Weight
  • Multienzyme Complexes / antagonists & inhibitors
  • Multienzyme Complexes / chemistry
  • Multienzyme Complexes / isolation & purification*
  • Phospholipases / genetics
  • Substrate Specificity
  • Virulence / genetics

Substances

  • Glycoproteins
  • Multienzyme Complexes
  • Acyltransferases
  • Phospholipases
  • Lysophospholipase
  • lysophospholipase-transacylase