CATALYSIS BY HUMAN-LEUKOCYTE ELASTASE .3. STEADY-STATE KINETICS FOR THE HYDROLYSIS OF PARA-NITROPHENYL ESTERS
CATALYSIS BY HUMAN-LEUKOCYTE ELASTASE .3. STEADY-STATE KINETICS FOR THE HYDROLYSIS OF PARA-NITROPHENYL ESTERS
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DOI：
10.1016/0003-9861(85)90673-3
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发表时间：
1985-01-01
影响因子：
3.9
通讯作者：
STEIN, RL
中科院分区：
文献类型：
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作者：
STEIN, RL
测定了pH值为7.4和25℃时的稳态动力学参数。C为人白细胞弹性酶催化水解几种n -碳苯氧基- l -氨基酸对硝基苯酯。这些酯的底物特异性相当广泛，包括Gly、Phe和Tyr衍生物。再加上对肽基底物的p -1特异性更窄的报道，这些结果表明，酶与底物之间的剪切键之间的相互作用调节了初级特异性。kc和kc/Km对底物结构的依赖性不明显。在白细胞弹性酶催化的反应中，酰化和去酰化在P-1特异性上有明显差异。
Steady-state kinetic parameters were determined at pH 7.4 and 25.degree. C for the human leukocyte elastase-catalyzed hydrolysis of several N-carbobenzoxy-L-amino acid p-nitrophenyl esters. The substrate specificity for these esters was quite broad, and included the Gly, Phe and Tyr derivatives. Together with reports of a much narrower P-1-specificity for peptide-based substrates, these results suggest that interactions remote from the scissle bond between enzyme and substrate regulate primary specificity. kc and kc/Km did not exhibit the same dependence on substrate structure. There apparently are significant differences in P-1 specificity between acylation and deacylation for leukocyte elastase-catalyzed reactions.