Enzymatic inactivation of substance P by a partially purified enzyme from rat brain.
Enzymatic inactivation of substance P by a partially purified enzyme from rat brain.
复制标题
通过大鼠脑中部分纯化的酶使 P 物质酶失活。
DOI：
10.1016/s0006-291x(75)80073-8
复制
发表时间：
1975
影响因子：
3.1
通讯作者：
N. Marks
中科院分区：
文献类型：
--
作者：
M. Benuck;N. Marks
P物质是一种具有强效中枢神经系统作用的单肽，可被大鼠脑匀浆迅速灭活，释放出包括Met. NH 2在内的所有氨基酸。在DEAE-纤维素上纯化存在于100，000 g上清液中的失活酶，并与降解血红蛋白和组蛋白的中性内肽酶平行洗脱。分解后，使用能够分离Met. NH 2和Leu-Met的方法测量释放的氨基酸。NH2 Phe和Leu的优先释放表明在两个或更多个内部位点（-Gln 6-Phe 7-或-Phe 7-Phe 8-和-Gly 9-Leu 10-）处裂解，并释放中间肽基产物。失活后游离Met的存在是由于Met. NH 2从P物质中释放后脱酰胺所致。Arg 1和Pro 2的缓慢释放表明Arg 1-Pro 2键仅被脑氨肽酶缓慢裂解。
Substance P, a unidecapeptide with potent CNS action, is rapidly inactivated by rat brain homogenate with release of all amino acids including Met.NH2. The inactivating enzyme present in the 100,000gsupernatant was purified on DEAE-cellulose and was eluted in parallel with a neutral endopeptidase degrading hemoglobin and histone. Breakdown was followed by measurement of amino acids released using a method capable of resolving Met.NH2and Leu-Met. NH2. The preferential release of Phe and Leu indicated cleavage at two or more internal sites (-Gln6-Phe7- or -Phe7-Phe8- and -Gly9-Leu10-) with release of intermediate peptidyl products. The presence of free Met following inactivation resulted from the deamidation of Met.NH2after its liberation from Substance P. A slow release of Arg1and Pro2indicated that the Arg1-Pro2bond is only slowly cleaved by brain aminopeptidases.