Yanagihara Y, Taniyama T, Misaki H, Suzuki Y, Matsumoto M, Mifuchi I
Microbiol Immunol. 1984;28(7):747-56. doi: 10.1111/j.1348-0421.1984.tb00730.x.
The hydrolysis of phosphatidylethanolamine, phosphatidylcholine, lysophosphatidylcholine, and trioleoylglycerol by Leptospira biflexa strain Urawa was studied in vitro. Phospholipase A1 was identified by the formation of 32P- and 14C-labeled lysoderivatives from 32P-phosphatidylcholine, 32P-phosphatidylethanolamine, or 1-acyl-2-[1-14C]oleoyl-sn-glycero-3-phosphorylcholine. Phospholipase A1 activity was independent of lipase in the microorganism since 14C-labeled trioleoylglycerol was scarcely attacked under the same conditions in which the phospholipids were hydrolyzed. Lysophospholipase activity was also demonstrated using 32P- and non-labeled lysophosphatidylcholine. The activity of phospholipase A1 was found in a broad range of pH but no optimal pH was determined. The pH optimum of lysophospholipase was 8.0. Both enzymes were labile to heat. Phospholipase C activity, however, could not be detected because no radioactive di- and monoacylglycerol was found in the experiment with 1-acyl-2-[1-14C]-oleoyl-sn-glycero-3-phosphorylcholine as the substrate. It was inferred that phosphatidylethanolamine, which was the major component of phospholipids in leptospirae, was hydrolyzed serially by phospholipase A (A1 and/or A2?) and lysophospholipase to glycerophosphorylethanolamine via 2-acyl-type-lyso-derivative as one metabolic pathway of the substrate.
对双曲钩端螺旋体浦原株体外水解磷脂酰乙醇胺、磷脂酰胆碱、溶血磷脂酰胆碱和三油酰甘油的情况进行了研究。通过从32P-磷脂酰胆碱、32P-磷脂酰乙醇胺或1-酰基-2-[1-14C]油酰基-sn-甘油-3-磷酸胆碱形成32P和14C标记的溶血衍生物来鉴定磷脂酶A1。微生物中的磷脂酶A1活性与脂肪酶无关，因为在水解磷脂的相同条件下，14C标记的三油酰甘油几乎未被攻击。使用32P和未标记的溶血磷脂酰胆碱也证明了溶血磷脂酶活性。发现磷脂酶A1的活性在很宽的pH范围内存在，但未确定最适pH。溶血磷脂酶的最适pH为8.0。两种酶对热都不稳定。然而，由于在以1-酰基-2-[1-14C]-油酰基-sn-甘油-3-磷酸胆碱为底物的实验中未发现放射性二酰基甘油和单酰基甘油，因此未检测到磷脂酶C活性。据推测，磷脂酰乙醇胺是钩端螺旋体中磷脂的主要成分，它通过磷脂酶A（A1和/或A2？）和溶血磷脂酶依次水解，经2-酰基型溶血衍生物生成甘油磷酸乙醇胺，这是底物的一种代谢途径。
