期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1981
卷号:78
期号:1
页码:120-123
DOI:10.1073/pnas.78.1.120
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1 ] was solubilized from a rat brain homogenate with sodium deoxycholate. This solubilized preparation had no detectable enzymic activity with either Mg-ATP or Mn-ATP as substrate. The activity could be restored by addition of either nonionic detergent or certain specific phospholipids. Maximal restoration of enzyme activity was obtained with Triton X-100, L-alpha-phosphatidylcholine, L-alpha-lysophosphatidylcholine, phosphatidyl-N-monomethylethanolamine, or sphingomyelin. Activity was only partially restored by phosphatidylethanolamine (40-60%) or phosphatidyl-N,N-dimethylethanolamine (10-20%). Other phospholipids tested, including phosphatidylserine, phosphatidylglycerol, phosphatidylinositol, and phosphatidic acid, could not restore enzyme activity but, instead, could inhibit the stimulation of enzyme activity by phosphatidylcholine. The restoration of activity by L-alpha-phosphatidylcholine was inhibited by cholesterol at concentrations above 33 mol %, although this effect was not observed with three different esters of cholesterol. These studies suggest a possible specific role of phospholipids in modulating adenylate cyclase activity.