Cook L, Ternai B
Chemistry Department, La Trobe University, Bundoora, Australia.
Biochem Int. 1988 Oct;17(4):637-46.
Brij 35 significantly reduced the inhibitory activity of hydrophobic alkyl 2-pyrones, oleic acid and alkyl peptides towards human sputum and leucocyte elastase, whereas 4-methoxy-6-(2'-hydroxy-2'-(carbobutyloxy)-vinyl)-2-pyrone, alpha-1-proteinase inhibitor and a sulfated chitosan were unaffected. The effect of Brij 35 on elastase appeared to be irreversible, since dialysis against Brij-free buffer was not accompanied by a return to inhibitory activity by the first group of inhibitors. However, passage through an ionic-exchange column was effective in removing the detergent from the enzyme. Brij 35 is also an activator of the elastases: kcat for Boc-Ala-4-nitrophenyl ester and methylsuccinyl-Ala-Ala-Pro-Val-4-nitroanilide increased by 20% and 40%, respectively in the presence of 0.015% Brij 35. Binding of the substrates to the enzyme is unaffected, since Km is unchanged.
Brij 35能显著降低疏水性烷基2-吡喃酮、油酸和烷基肽对人痰液和白细胞弹性蛋白酶的抑制活性，而4-甲氧基-6-(2'-羟基-2'-(羧丁氧基)-乙烯基)-2-吡喃酮、α-1-蛋白酶抑制剂和硫酸化壳聚糖则不受影响。Brij 35对弹性蛋白酶的作用似乎是不可逆的，因为用不含Brij的缓冲液透析后，第一组抑制剂的抑制活性并未恢复。然而，通过离子交换柱可有效去除酶中的去污剂。Brij 35还是弹性蛋白酶的激活剂：在0.015% Brij 35存在下，Boc-Ala-4-硝基苯酯和甲基琥珀酰-Ala-Ala-Pro-Val-4-硝基苯胺的kcat分别增加了20%和40%。由于Km不变，底物与酶的结合不受影响。
