title: Glycylprolyl dipeptidase activity of Bacteroides gingivalis W50 and the avirulent variant W50/BEI.
abstract: Glycylprolyl dipeptidase activity was measured in cells, extracellular vesicles (ECV) and the soluble extracellular protein fraction (EP) of batch cultures of strains W50 and W50/BEI. Total culture enzyme activity of W50 dropped with age whilst that of W50/BEI remained constant. Activity was highest in the cellular fraction, greater for W50/BEI than W50 and rose with culture age. Both strains showed similar ECV activities but these declined with culture age. The EP glycylprolyl dipeptidase activity of W50/BEI in older cultures rose to a level 13-fold greater than W50. The majority of extracellular activity was represented by the ECV for strain W50 but by EP for W50/BEI. Variable but incomplete attenuation of activity was achieved by dithiothreitol. ECV and EP activities were associated with a high molecular mass fraction, but a smaller fraction (molecular mass 30,000) was detected in W50/BEI EP.
authors.affiliation: Department of Dental Sciences, University of Liverpool, U.K.
authors.forename: H M
authors.initials: HM
authors.lastname: Kay
authors.forename: A J
authors.initials: AJ
authors.lastname: Birss
authors.forename: J W
authors.initials: JW
authors.lastname: Smalley
mesh_terms: D001439:Bacteroides / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D004229:Dithiothreitol / Q000494:pharmacology; D014644:Genetic Variation; D006651:Histocytochemistry; D008970:Molecular Weight; D014774:Virulence
chemical_list: D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; C059607:glycylprolyl dipeptidase; D004229:Dithiothreitol