In vitro and ex vivo inhibition of hepatitis A virus 3C proteinase by a peptidyl monofluoromethyl ketone
作者:Tina S Morris、Sven Frormann、Shirley Shechosky、Christopher Lowe、Manjinder S Lall、Verena Gauss-Müller、Robert H Purcell、Suzanne U Emerson、John C Vederas、Bruce A Malcolm
DOI:10.1016/s0968-0896(97)88649-x
日期:1997.5
configuration like those of the mammalian serine proteinases (Malcolm, B. A. Protein Science 1995, 4, 1439). A peptidyl monofluoromethyl ketone (peptidyl-FMK) based on the preferred peptide substrates for HAV 3C proteinase was generated by first coupling the precursor, N,N-dimethylglutamine fluoromethylalcohol, to the tripeptide, Ac-Leu-Ala-Ala-OH, and then oxidizing the product to the corresponding peptidyl-FMK
甲型肝炎病毒(HAV)3C蛋白酶是负责处理病毒多蛋白的酶。尽管是半胱氨酸蛋白酶,但它表现出类似于哺乳动物丝氨酸蛋白酶的活性位点构型(Malcolm,BA Protein Science 1995,4,1439)。通过首先将前体N,N-二甲基谷氨酰胺氟甲基醇与三肽Ac-Leu-Ala-Ala-OH偶联,然后生成基于HAV 3C蛋白酶优选肽底物的肽基单氟甲基酮(peptidyl-FMK)。将产物氧化为相应的肽基-FMK(Ac-LAAQ'-FMK)。发现该分子是HAV 3C的不可逆灭活剂,其二级速率常数为3.3 x 10(2)M-1 s-1。19 F NMR光谱表明在氟甲基酮使酶失活时氟化物的置换。13C标记的抑制剂和HAV 3C蛋白酶之间的复合物的NMR光谱表明形成了(烷硫基)甲基酮。使用体外转录/翻译产生的各种底物进行的多蛋白加工研究表明,即使是最快速的蛋白水解事件,如2A-2B和2C-3A