title: regT can modulate gingipain activity and response to oxidative stress in Porphyromonas gingivalis.
abstract: Recombinant VimA protein can interact with the gingipains and several other proteins that may play a role in its biogenesis in Porphyromonas gingivalis. In silico analysis of PG2096, a hypothetical protein that was shown to interact with VimA, suggests that it may have environmental stress resistance properties. To further evaluate the role(s) of PG2096, the predicted open reading frame was PCR amplified from P. gingivalis W83 and insertionally inactivated using the ermF-ermAM antibiotic-resistance cassette. One randomly chosen PG2096-defective mutant created by allelic exchange and designated FLL205 was further characterized. Under normal growth conditions at 37&emsp14;°C, Arg-X and Lys-X gingipain activities in FLL205 were reduced by approximately 35 % and 21 %, respectively, compared to the wild-type strain. However, during prolonged growth at an elevated temperature of 42&emsp14;°C, Arg-X activity was increased by more than 40 % in FLL205 in comparison to the wild-type strain. In addition, the PG2096-defective mutant was more resistant to oxidative stress when treated with 0.25&emsp14;mM hydrogen peroxide. Taken together these results suggest that the PG2096 gene, designated regT (regulator of gingipain activity at elevated temperatures), may be involved in regulating gingipain activity at elevated temperatures and be important in oxidative stress resistance in P. gingivalis.
authors.affiliation: Department of Biological Sciences, Oakwood University, Huntsville, AL 35896, USA.
authors.forename: E
authors.initials: E
authors.lastname: Vanterpool
authors.affiliation: Department of Basic Sciences, Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA.
authors.forename: A Wilson
authors.initials: AW
authors.lastname: Aruni
authors.affiliation: Department of Basic Sciences, Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA.
authors.forename: F
authors.initials: F
authors.lastname: Roy
authors.affiliation: Department of Basic Sciences, Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Fletcher
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D000080867:Gingipain Cysteine Endopeptidases; D006358:Hot Temperature; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009154:Mutation; D018384:Oxidative Stress; D010447:Peptide Hydrolases / Q000378:metabolism; D016966:Porphyromonas gingivalis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D018829:Adhesins, Bacterial; D000080867:Gingipain Cysteine Endopeptidases; D010447:Peptide Hydrolases; D003546:Cysteine Endopeptidases