title: A C69-family cysteine dipeptidase from Lactobacillus farciminis JCM1097 possesses strong Gly-Pro hydrolytic activity.
abstract: Dipeptide Gly-Pro, a hard-to-degrade and collagenous peptide, is thought to be hydrolysed by prolidases that can work on various X-Pro dipeptides. Here, we found an entirely different type of dipeptidase from Lactobacillus farciminis JCM1097 that cleaves Gly-Pro far more efficiently and with higher specificity than prolidases, and then investigated its properties by use of a recombinant enzyme. Although L. farciminis dipeptidase was expressed in the form of an inclusion body in Escherichia coli at 37 °C, it was smoothly over-expressed in a soluble form at a lower temperature. The maximal Gly-Pro hydrolytic activity was attained in E. coli at 30 °C. In contrast to prolidases that are metallopeptidases showing the modest or marginal activity toward Gly-Pro, this L. farciminis dipeptidase belongs to the cysteine peptidase family C69. Lactobacillus farciminis dipeptidase occurs in cytoplasm and utilizes the side chain of an amino-terminal cysteine residue to perform the nucleophilic attack on the target amide bond between Gly-Pro after processing eight amino acid residues at the N-terminus. Furthermore, L. farciminis dipeptidase is potent enough to synthesize Gly-Pro from Gly and Pro by a reverse reaction. These novel properties could be revealed by virtue of the success in preparing recombinant enzymes in higher yield and in a stable form.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University; and Health Research Institute, National Institute of Advanced Industrial Science and Technology.
authors.forename: Takuma
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Takuya
authors.initials: T
authors.lastname: Otokawa
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kono
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Shigeri
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Watanabe
mesh_terms: D003545:Cysteine / Q000378:metabolism*; D004150:Dipeptidases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004151:Dipeptides / Q000737:chemistry* / Q000378:metabolism*; D006868:Hydrolysis; D007778:Lactobacillus / Q000201:enzymology*; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D013379:Substrate Specificity
chemical_list: D004151:Dipeptides; D004150:Dipeptidases; D003545:Cysteine