Inactivation of vimF, a putative glycosyltransferase gene downstream of vimE, alters glycosylation and activation of the gingipains in Porphyromonas gingivalis W83.
Regulation/activation of the Porphyromonas gingivalis gingipains is poorly understood. A 1.2-kb open reading frame, a putative glycosyltransferase, downstream of vimE, was cloned, insertionally inactivated using the ermF-ermAM antibiotic resistance cassette, and used to create a defective mutant by allelic exchange. In contrast to the wild-type W83 strain, this mutant, designated P. gingivalis FLL95, was nonpigmented and nonhemolytic when plated on Brucella blood agar. Arginine- and lysine-specific gingipain activities were reduced by approximately 97% and 96%, respectively, relative to that of the parent strain. These activities were unaffected by the growth phase, in contrast to the vimA-defective mutant P. gingivalis FLL92. Expression of the rgpA, rgpB, and kgp gingipain genes was unaffected in P. gingivalis FLL95 in comparison to the wild-type strain. In nonactive gingipain extracellular protein fractions, multiple high-molecular-weight proteins immunoreacted with gingipain-specific antibodies. The specific gingipain-associated sugar moiety recognized by monoclonal antibody 1B5 was absent in FLL95. Taken together, these results suggest that the vimE downstream gene, designated vimF (virulence modulating gene F), which is a putative glycosyltransferase group 1, is involved in the regulation of the major virulence factors of P. gingivalis.
Vanterpool
Elaine
E
Department of Biochemistry and Microbiology, School of Medicine, Loma Linda University, Loma Linda, California 92350, USA. eguiness02x@som.llu.edu
Roy
Francis
F
Fletcher
Hansel M
HM
D018829:Adhesins, Bacterial; D000483:Alleles; D019295:Computational Biology; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D004789:Enzyme Activation; D005353:Fibronectins / Q000378:metabolism; D000080867:Gingipain Cysteine Endopeptidases; D006031:Glycosylation; D016695:Glycosyltransferases / Q000235:genetics*; D006384:Hemagglutination; D006388:Hemagglutinins / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D016966:Porphyromonas gingivalis / Q000378:metabolism / Q000472:pathogenicity*; D037521:Virulence Factors / Q000235:genetics*
D018829:Adhesins, Bacterial; D005353:Fibronectins; D000080867:Gingipain Cysteine Endopeptidases; D006388:Hemagglutinins; D037521:Virulence Factors; D016695:Glycosyltransferases; D003546:Cysteine Endopeptidases