Tetratricopeptide repeat protein-associated proteins contribute to the virulence of Porphyromonas gingivalis.
Porphyromonas gingivalis is one of the most etiologically important microorganisms in periodontal disease. We found in a previous study that PG1385 (TprA) protein, a tetratricopeptide repeat (TPR) protein, was upregulated in P. gingivalis wild-type cells placed in a mouse subcutaneous chamber and that a tprA mutant was clearly less virulent in the mouse subcutaneous abscess model (M. Yoshimura et al., Oral Microbiol. Immunol. 23:413-418, 2008). In the present study, we investigated the gene expression profile of tprA mutant cells placed in a mouse subcutaneous chamber and found that 9 genes, including PG2102 (tapA), PG2101 (tapB), and PG2100 (tapC) genes, were downregulated in the tprA mutant compared with those in the wild type. Expression of a cluster of tapA, tapB, and tapC genes of the mutant was also downregulated in an in vitro culture with enriched brain heart infusion medium. The TprA protein has three TPR motifs known as a protein-protein interaction module. Yeast two-hybrid system analysis and in vitro protein binding assays with immunoprecipitation and surface plasmon resonance detection revealed that the TprA protein could bind to TapA and TapB proteins. TprA and TapB proteins were located in the periplasmic space, whereas TapA, which appeared to be one of the C-terminal domain family proteins, was located at the outer membrane. We constructed tapA, tapB, and tapC single mutants and a tapA-tapB-tapC deletion mutant. In the mouse subcutaneous infection experiment, all of the mutants were less virulent than the wild type. These results suggest that TprA, TapA, TapB, and TapC are cooperatively involved in P. gingivalis virulence.
Kondo
Yoshio
Y
Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan.
Ohara
Naoya
N
Sato
Keiko
K
Yoshimura
Mamiko
M
Yukitake
Hideharu
H
Naito
Mariko
M
Fujiwara
Taku
T
Nakayama
Koji
K
D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D016866:Bacteroidaceae Infections / Q000382:microbiology; D003470:Culture Media / Q000737:chemistry; D005260:Female; D017353:Gene Deletion; D020869:Gene Expression Profiling; D047468:Immunoprecipitation; D051379:Mice; D008807:Mice, Inbred BALB C; D019897:Periplasm / Q000737:chemistry; D016966:Porphyromonas gingivalis / Q000472:pathogenicity*; D011485:Protein Binding; D025941:Protein Interaction Mapping; D018461:Soft Tissue Infections / Q000382:microbiology; D020349:Surface Plasmon Resonance; D020798:Two-Hybrid System Techniques; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D003470:Culture Media; D037521:Virulence Factors