The effect of limited proteolysis on enzymatic, binding and immunological properties of ligandin.
The effect of limited proteolysis on enzymatic, binding and immunological properties of ligandin.
复制标题
有限蛋白水解对配体蛋白的酶促、结合和免疫学特性的影响。
DOI：
10.1016/0006-291x(82)90670-2
复制
发表时间：
1982
影响因子：
3.1
通讯作者：
Arias,IM
中科院分区：
文献类型：
--
作者：
Bhargava,MM;Ohmi,N;Arias,IM
The peptide mixture obtained from controlled proteolytic digestion of ligandin with proteinase K or subtilisin retained 40% of glutathione-S-transferase and steroid isomerase activities, immunological reactivity and lower affinity bilirubin binding but binding at the primary site was abolished. When these limited proteolytic digests, which had no intact ligandin as determined by SDS gel electrophoresis, were subjected to Sephadex G-75 column chromatography, 40–50% of the peptide fragments were recovered in fractions where intact ligandin eluted. The results suggest that intact ligandin is not required for enzymatic activities, binding of bilirubin at the secondary site, or immunological reactivity; steroid isomerase and glutathione-S-transferase activities are modulated in a parallel manner and may be mediated by the same region of the protein, and primary and secondary binding sites for bilirubin are distinct and independent, despite nicks introduced by proteolysis in ligandin's subunits, some of the fragments remain associated under non-denaturing conditions and the susceptibility of the two subunits to the proteases is different.
