Powers J C, Kam C M
School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta 30332, USA.
Methods Enzymol. 1995;248:3-18. doi: 10.1016/0076-6879(95)48003-x.
Peptide thioesters are sensitive substrates of various serine peptidases and metalloendopeptidases. Thioester substrates generally have high enzymatic hydrolysis rates and low background hydrolysis rates, and the hydrolysis rates can be easily monitored in the presence of thiol reagents such as 4,4'-dithiodipyridine or 5,5'-dithiobis (2-nitrobenzoic acid). Peptide thioester substrates have been invaluable for the study of enzyme specificity and enzyme inhibitors, especially in cases where no other practical synthetic substrates are available. Tripeptide substrates of the type Boc-Ala-Ala-AA-SBzl, where AA is nearly all of the 20 common amino acids, have now been synthesized and should be useful for the subsite mapping of new serine peptidases and the study of crude cell preparations containing serine peptidases.
肽硫酯是多种丝氨酸肽酶和金属内肽酶的敏感底物。硫酯底物通常具有较高的酶促水解速率和较低的背景水解速率，并且在存在硫醇试剂（如4,4'-二硫代二吡啶或5,5'-二硫代双（2-硝基苯甲酸））的情况下，水解速率可以很容易地监测。肽硫酯底物对于酶特异性和酶抑制剂的研究非常重要，特别是在没有其他实用合成底物可用的情况下。已合成了Boc-Ala-Ala-AA-SBzl类型的三肽底物，其中AA几乎涵盖了所有20种常见氨基酸，这些底物应有助于新丝氨酸肽酶的亚位点定位以及对含有丝氨酸肽酶的粗细胞制剂的研究。
