Cloning and DNA sequence analysis of an X-prolyl dipeptidyl aminopeptidase gene from Lactococcus lactis subsp. lactis NCDO 763.
Lactococcus lactis subsp. lactis NCDO 763 (also designated ML3) possesses an X-prolyl dipeptidyl aminopeptidase (X-PDAP; EC 3.4.14.5). X-PDAP mutants were selected by an enzymatic plate assay on the basis of their inability to hydrolyze an L-phenylalanyl-L-proline-beta-naphthylamide substrate. A DNA bank from L. lactis subsp. lactis NCDO 763 was constructed in one of these X-PDAP mutants, and one clone in which the original X-PDAP phenotype was restored was detected by the enzymatic plate assay. The X-PDAP gene, designated pepXP, was further subcloned and sequenced. It codes for a protein containing 763 residues. Comparison of the amino-terminal sequence of the X-PDAP enzyme with the amino acid sequence deduced from the pepXP gene indicated that the enzyme is not subjected to posttranslational modification or exported via processing of a signal peptide. The pepXP gene from L. lactis subsp. lactis NCDO 763 in more than 99% homologous to the pepXP gene from L. lactis subsp. cremoris P8-2-47 described elsewhere (B. Mayo, J. Kok, K. Venema, W. Bockelmann, M. Teuber, H. Reinke, and G. Venema, Appl. Environ. Microbiol. 57:38-44, 1991) and is also conserved in other lactococcal strains.
Nardi
M
M
Station de Recherches Laitières Institut National de la Recherche Agronomique, Jouy-en-Josas, France.
Chopin
M C
MC
Chopin
A
A
Cals
M M
MM
Gripon
J C
JC
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics*; D018819:Dipeptidyl Peptidase 4; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D013294:Lactococcus lactis / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
D004269:DNA, Bacterial; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D018819:Dipeptidyl Peptidase 4