chymotrypsin-like活动的比较研究鼠肝脏multicatalytic蛋白酶和ClpP大肠杆菌。
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Arribas J, Castano詹
chymotrypsin-like活动的比较研究鼠肝脏multicatalytic蛋白酶和ClpP大肠杆菌。
生物化学杂志。1993年10月5日;268 (28):21165 - 71。
- PubMed ID
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8407953 (在PubMed]
- 文摘
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chymotrypsin-like活动的比较研究纯化重组ClpP蛋白酶和multicatalytic蛋白酶从鼠肝脏。肽酶活性的酶与几个合成fluorogenic肽,分析了含有芳香族或非极性氨基酸的P1的位置。各自的Vmax,公里,Vmax /公里计算动力学实验。multicatalytic蛋白酶的底物特异性,表达的Vmax / Km值,表明以下衬底偏好:N-Suc-IIW-MCA > N-Suc-LY-MCA > N-Suc-LLVY-MCA >或= N-Suc-AAF-MCA > N-Cbz-GGL-beta-NA > Glut-GGF-beta-NA > FPAM-4-MNA。对于ClpP优先的顺序是:N-Suc-LY-MCA > N-Suc-IIW-MCA > N-Suc-LLVY-MCA > = N-Suc-AAF-MCA >或= N-Cbz-GGL-beta-NA > FPAM-4-MNA(地点:N-Suc N-succinyl -;MCA, 7-amido-4-methyl香豆素;beta-NA beta-naphthylamide;N-Cbz N-benzyloxycarbonyl -;4-MNA 4-methoxy-beta-naphthylamide;过剩,glutaryl。 This similar substrate specificity is further supported by the lack of activity of both enzymes against SY-MCA and N-Suc-AAPF-MCA (known substrates of chymotrypsin), by very reduced activity against N-Suc-AAA-MCA and by no significant activity against LG-beta-NA. The results of mixed substrate experiments have shown that all the peptides that are substrates seem to be hydrolyzed by a single class of chymotrypsin-like site in both enzymes. The substrate specificity studies suggest a possible evolutionary relationship between the catalytic component of the ClpP of Escherichia coli and the multicatalytic proteinase chymotrypsin-like catalytic component. This conclusion is further supported by other circumstantial evidence: the fact that affinity-purified anti-ClpP antibodies cross-react with two polypeptide components of the rat liver multicatalytic proteinase complex, presented here and also shown previously; the known resemblance of both structures at the electron microscope level; and their reported role in the degradation of NH2-end rule substrates.