Narayanan A S, Anwar R A
Biochem J. 1969 Aug;114(1):11-7. doi: 10.1042/bj1140011.
An electrophoretically homogeneous elastase preparation free from tryptic and chymotryptic activities was obtained by chromatography on DEAE-Sephadex and CM-cellulose. This preparation exhibits a narrower specificity towards peptide bonds than that observed by Naughton & Sanger (1961). With oxidized insulin B chain as substrate, the fastest breaks occur between alanine-14 and leucine-15 and between valine-18 and cysteic acid-19. The bond between glycine-23 and phenylalanine-24 is also efficiently hydrolysed. Other bonds hydrolysed are that between valine-12 and glutamic acid-13 and that between serine-9 and histidine-10. Oxidized insulin A chain is hydrolysed only at one of two points, between alanine-8 and serine-9 or between serine-12 and leucine-13, and the rate of hydrolysis is very low.
通过在DEAE-葡聚糖凝胶和CM-纤维素上进行色谱分离，获得了一种无胰蛋白酶和糜蛋白酶活性的电泳纯弹性蛋白酶制剂。该制剂对肽键的特异性比诺顿和桑格（1961年）观察到的更窄。以氧化胰岛素B链为底物时，最快的断裂发生在丙氨酸-14和亮氨酸-15之间以及缬氨酸-18和半胱氨酸-19之间。甘氨酸-23和苯丙氨酸-24之间的键也能被有效水解。其他被水解的键是缬氨酸-12和谷氨酸-13之间的键以及丝氨酸-9和组氨酸-10之间的键。氧化胰岛素A链仅在两个点之一被水解，即在丙氨酸-8和丝氨酸-9之间或丝氨酸-12和亮氨酸-13之间，且水解速率非常低。
