爱滋病病毒中肽段的酶促合成

Enztymatic Synthesis of HIV-Ⅰ Peptides

1937年,Bergmann和Fraenkel-Conrat首次用酶促法合成了羧酰苯胺键以来,由于该法对氨基酸的侧链无需保护,不会发生消旋等独特优点,酶促合成已经有了很大的发展。

The protease-catalyzed syntheses of three peptide derivatives. Boc-Leu-Ile-Cys(Bzl)-N_2H_2Ph(3a), Boc-Gly-Cys (Bzl)-Ser(Bzl)-Gly-Lys (Z)-N_2H_2Ph (8a) and Z-Leu-Gly-Leu-Trp-N_2H_2Ph(12a), from amino acid sequence 598～609 of gp 41 of Human Im-munodeficiency Virus-I(HIV-I), are reported. The C-terminal phenylhydrazide, as well asall the peptide bonds were constructed by papain-mediated synthesis via stepwise elongation.To suppress the side reaction of the secondary hydrolysis, the N~α-protected amino acid es-ters were used as carboxyl components to react with the nucleophiles, amino acid or peptidephenylhydrazides, in an alkaline media. It was also found that CH_3CN was more suitablethan CH_3OH for the enzymatic peptide synthesis. For comparison. two of them (3a and8a) were also synthesized by the conventional DCCI method. The products obtained fromboth methods were shown to be identical by several criteria.