Department of Applied Microbial Technology, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082, Japan.
Department of Life Science, Faculty of Science and Engineering, Setsunan University, Neyagawa, Osaka, Japan.
Appl Biochem Biotechnol. 2018 Jan;184(1):239-252. doi: 10.1007/s12010-017-2547-8. Epub 2017 Jul 3.
Tripeptidyl peptidase (TPP) is an exopeptidase that sequentially hydrolyzes tripeptides from the N-terminus of oligopeptides or polypeptides. We performed screening for isolating novel TPP-producing microorganisms from soil samples. TPP activity was observed in the culture supernatant of Streptomyces herbaricolor TY-21 by using Ala-Ala-Phe-p-nitroanilide (pNA) as the substrate. TPP from the culture supernatant was purified to approximately 790-fold. It was shown to cleave oxidized insulin B-chain, thereby with releasing tripeptide units, but not the N-terminal-protected peptide, Cbz-Ala-Ala-Phe-pNA. The TPP gene, designated tpp, was isolated from a partial genomic DNA library of S. herbaricolor TY-21. The TPP gene consisted of 1488 bp, and encoded a 133-amino acid pre-pro-peptide and a 362-amino acid mature enzyme containing conserved amino acid residues (Asp-36, His-77, and Ser-282) similar to the catalytic residues in subtilisin. TY-21 TPP belonged to the peptidase S8A family in the MEROPS database. The mature TY-21 TPP showed approximately 49% identity with tripeptidyl peptidase subtilisin-like (TPP S) from Streptomyces lividans strain 66.
三肽酰肽酶（TPP）是一种外肽酶，它从寡肽或多肽的 N 末端依次水解三肽。我们从土壤样品中筛选分离出新型 TPP 产生微生物。用 Ala-Ala-Phe-p-硝基苯胺（pNA）作为底物，在链霉菌 TY-21 的培养上清液中观察到 TPP 活性。从培养上清液中纯化 TPP 约 790 倍。它能切割氧化胰岛素 B 链，从而释放三肽单元，而不是 N 末端保护的肽 Cbz-Ala-Ala-Phe-pNA。TPP 基因，命名为 tpp，从链霉菌 TY-21 的部分基因组 DNA 文库中分离得到。TPP 基因由 1488 bp 组成，编码一个 133 个氨基酸的前导肽和一个 362 个氨基酸的成熟酶，其中包含保守的氨基酸残基（Asp-36、His-77 和 Ser-282），类似于枯草杆菌蛋白酶中的催化残基。TY-21 TPP 在 MEROPS 数据库中属于肽酶 S8A 家族。成熟的 TY-21 TPP 与来自链霉菌 lividans 株 66 的三肽酰肽酶枯草杆菌蛋白酶样（TPP S）约有 49%的同一性。
