Purification and characterization of lysophospholipase-transacylase (h-LPTA) from a highly virulent strain of Candida albicans.
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.
Mirbod
F
F
Department of Dermatology, Gifu University School of Medicine, Japan.
Banno
Y
Y
Ghannoum
M A
MA
Ibrahim
A S
AS
Nakashima
S
S
Kitajima
Y
Y
Cole
G T
GT
Nozawa
Y
Y
D000217:Acyltransferases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification*; D002176:Candida albicans / Q000201:enzymology* / Q000235:genetics; D002177:Candidiasis / Q000382:microbiology; D006023:Glycoproteins / Q000302:isolation & purification; D007700:Kinetics; D008245:Lysophospholipase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification*; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification*; D010740:Phospholipases / Q000235:genetics; D013379:Substrate Specificity; D014774:Virulence / Q000235:genetics
D006023:Glycoproteins; D009097:Multienzyme Complexes; D000217:Acyltransferases; D010740:Phospholipases; D008245:Lysophospholipase; C021782:lysophospholipase-transacylase