Suc-Ala-Ala-Pro-Leu-pNA is a kind of peptidyl p-nitroanilide substrate in the human seminal plasma (HSP) which can be hydrolyzed by acyl amidase-like leucine aminopeptidase [1]. Suc-Ala-Ala-Pro-Leu-pNA amidolytic activity can be inhibited by some proteinase inhibitors like Amastatin and Actinonin [1]. The recent study indicates that some azoospermia samples showed a very high Suc-Ala-Ala-Pro-Leu-pNA amidolytic activity which may related to the possible causes for azoospermia [2].
References:
[1] Matsuda Y, Katayama M, Hara I, et al. Inhibitors on an elastase-like enzyme activity catalyzing Suc-Ala-Ala-Pro-Leu-pNA amidolysis in human seminal plasma [J]. Archives of andrology, 2000, 44(1): 1-9.
[2] Ishikawa H, Matsuda Y, Katayama M, et al. Amidolytic activities and prostate-specific antigen in human seminal plasma [J]. Archives of andrology, 1999, 43(2): 141-151.
Suc-Ala-Ala-Pro-Leu-pNA是人类精浆（HSP）中的一种肽基对硝基苯胺底物，可被类酰基酰胺酶亮氨酸氨基肽酶水解[1]。Suc-Ala-Ala-Pro-Leu-pNA的酰胺水解活性能被某些蛋白酶抑制剂（如Amastatin和Actinonin）抑制[1]。近期有研究表明，一些无精症样本表现出极高的Suc-Ala-Ala-Pro-Leu-pNA水解活性，可能与无精症的潜在原因有关[2]。