Banbula A, Yen J, Oleksy A, Mak P, Bugno M, Travis J, Potempa J
Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA.
J Biol Chem. 2001 Mar 2;276(9):6299-305. doi: 10.1074/jbc.M008789200. Epub 2000 Nov 28.
A novel dipeptidylpeptidase (DPP-7) was purified from the membrane fraction of Porphyromonas gingivalis. This enzyme, with an apparent molecular mass of 76 kDa, has the specificity for both aliphatic and aromatic residues in the P1 position. Although it belongs to the serine class of peptidases, it does not resemble other known dipeptidylpeptidases. Interestingly, the amino acid sequence around the putative active site serine residue shows significant similarity to the C-terminal region of the Staphylococcus aureus V-8 endopeptidase. The genes encoding homologues of DPP-7 were found in genomes of Xylella fastidiosa, Shewanella putrefaciens, and P. gingivalis. It is likely that at least in P. gingivalis, DPP-7 and its homologue, in concert with other di- and tripeptidases, serve nutritional functions by providing dipeptides to this asaccharolytic bacterium.
一种新型二肽基肽酶（DPP - 7）从牙龈卟啉单胞菌的膜组分中纯化得到。这种酶的表观分子量为76 kDa，对P1位的脂肪族和芳香族残基均具有特异性。尽管它属于丝氨酸类肽酶，但与其他已知的二肽基肽酶并不相似。有趣的是，假定的活性位点丝氨酸残基周围的氨基酸序列与金黄色葡萄球菌V - 8内肽酶的C末端区域显示出显著的相似性。在木质部难养菌、腐败希瓦氏菌和牙龈卟啉单胞菌的基因组中发现了编码DPP - 7同源物的基因。至少在牙龈卟啉单胞菌中，DPP - 7及其同源物可能与其他二肽酶和三肽酶协同作用，通过为这种不分解糖类的细菌提供二肽来发挥营养功能。
