Jones R E, Plymate S R
Department of Medicine, Madigan Army Medical Center, Tacoma, Washington 98431-5000.
J Androl. 1989 Sep-Oct;10(5):346-50. doi: 10.1002/j.1939-4640.1989.tb00115.x.
To clarify the mechanism of phospholipid synthesis in spermatozoa, fresh human spermatozoa were incubated with labeled fatty acids and 1-acyl-lysophosphatidyl choline (LPC) in the presence or absence of coenzyme A (CoASH). Both docosahexaenoic acid and palmitic acid were incorporated into phosphatidylcholine; however, this reaction was absolutely dependent upon the presence of CoASH in the incubation medium. The rate of incorporation of docosahexaenoic acid was 2.7-fold higher than that of palmitic acid, but more palmitic acid was incorporated into phosphatidylcholine in the absence of LPC. These data provide direct evidence for acyl transferase activity in human spermatozoa and may furnish a mechanism for phospholipid remodeling in sperm membranes. The different incorporation rates of these fatty acids into phosphatidylcholine may be due to the kinetics of the activation step, long chain fatty acid:CoASH ligase (AMP), or the substrate specificity of the acyl transferase.
为阐明精子中磷脂合成的机制，将新鲜的人类精子与标记脂肪酸及1-酰基溶血磷脂酰胆碱（LPC）在有或没有辅酶A（CoASH）存在的情况下进行孵育。二十二碳六烯酸和棕榈酸均被掺入磷脂酰胆碱中；然而，该反应绝对依赖于孵育培养基中CoASH的存在。二十二碳六烯酸的掺入速率比棕榈酸高2.7倍，但在没有LPC的情况下，更多的棕榈酸被掺入磷脂酰胆碱中。这些数据为人类精子中的酰基转移酶活性提供了直接证据，并可能为精子膜中磷脂重塑提供一种机制。这些脂肪酸掺入磷脂酰胆碱的不同速率可能归因于活化步骤、长链脂肪酸：CoASH连接酶（AMP）的动力学，或酰基转移酶的底物特异性。
