II型胶原蛋白对蝌蚪胶原酶降解I型胶原蛋白的双重作用。

Dual effects of type II collagen on the degradation of type I collagen by tadpole collagenase.

作者信息

Sunada H, Hayashi T, Hori H, Nagai Y

出版信息

Coll Relat Res. 1981 Feb;1(2):177-85. doi: 10.1016/s0174-173x(81)80018-0.

Abstract

Kinetic analysis of the degradation of mixtures of type I and type II collagens by tadpole collagenase was performed, using [14C]glycine-labeled type I collagen and [3H]acetylated type II collagen as substrates. The degradation rate of type I collagen was decreased in the initial stage of the reaction, then further slowed down giving a constant rate independent of both the amounts of enzyme and type II collagen. The effect of type II collagen on the degradation of type I collagen is two-fold. First, competitive inhibition manifested only in the initial stage of the reaction due to higher (about 4-fold) affinity of type II collagen for the enzyme than type I collagen. Second, interference in step(s) following the formation of enzyme-substrate complex.

摘要

利用[14C]甘氨酸标记的I型胶原蛋白和[3H]乙酰化II型胶原蛋白作为底物，对蝌蚪胶原酶降解I型和II型胶原蛋白混合物进行了动力学分析。I型胶原蛋白的降解速率在反应初期降低，随后进一步减慢，达到一个与酶量和II型胶原蛋白量均无关的恒定速率。II型胶原蛋白对I型胶原蛋白降解的影响具有双重性。首先，竞争性抑制仅在反应初期表现出来，这是由于II型胶原蛋白对酶的亲和力比I型胶原蛋白高（约4倍）。其次，对酶-底物复合物形成后的步骤产生干扰。