Schuster M, Aaviksaar A, Stepanov V M, Rudenskaya G N, Jakubke H D
Department of Biochemistry, University of Leipzig, FRG.
Biomed Biochim Acta. 1991;50(2):139-43.
The S'-subsite specificity of the endoproteinase Glu/Asp-C from Actinomyces sp. was studied by acyl transfer reactions using amino-acid- and peptide-derived nucleophilic amino components. The following results were obtained: 1. The enzyme prefers amino acid amides with hydrophobic side chains in P'i position. In addition, positively charged functions in this position favour S'-P' interactions significantly. 2. Stereospecific binding is a prerequisite for nucleophilic efficiency. 3. Dipeptide amides are more efficient amino components in comparison to free dipeptides whereas oligoglycines show a poor nucleophilic behaviour independent of chain length.
利用氨基酸和肽衍生的亲核氨基成分通过酰基转移反应研究了来自放线菌属的内蛋白酶Glu/Asp-C的S'-亚位点特异性。获得了以下结果：1. 该酶更倾向于P'i位置具有疏水侧链的氨基酸酰胺。此外，该位置的带正电荷官能团显著促进S'-P'相互作用。2. 立体特异性结合是亲核效率的先决条件。3. 与游离二肽相比，二肽酰胺是更有效的氨基成分，而寡甘氨酸无论链长如何都表现出较差的亲核行为。
