start-ver=1.4 cd-journal=joma no-vol=12 cd-vols= no-issue= article-no= start-page=994014 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2022 dt-pub=20220913 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Cnm of Streptococcus mutans is important for cell surface structure and membrane permeability en-subtitle= kn-subtitle= en-abstract= kn-abstract=Streptococcus mutans, a Gram-positive facultative anaerobic bacterium, is a major pathogen of dental caries. The protein Cnm of S. mutans is involved in collagen binding, but its other biological functions are unknown. In this study, a Cnm-deficient isogenic mutant and a complementation strain were generated from a Cnm-positive S. mutans strain to help determine the properties of Cnm. Initially, comparison of the cell surface structure was performed by electron microscopy, which demonstrated that Cnm appears to be localized on the cell surface and associated with a protruding cell surface structure. Deep RNA sequencing of the strains revealed that the defect in Cnm caused upregulated expression of many genes related to ABC transporters and cell-surface proteins, while a few genes were downregulated. The amount of biofilm formed by the Cnm-defective strain increased compared with the parental and complemented strains, but the biofilm structure was thinner because of elevated expression of genes encoding glucan synthesis enzymes, leading to increased production of extracellular polysaccharides. Particular antibiotics, including bacitracin and chloramphenicol, had a lower minimum inhibitory concentration for the Cnm-defective strain than particular antibiotics, including bacitracin and chloramphenicol, compared with the parental and complemented strains. Our results suggest that S. mutans Cnm is located on the cell surface, gives rise to the observed protruding cell surface, and is associated with several biological properties related to membrane permeability. en-copyright= kn-copyright= en-aut-name=NakaShuhei en-aut-sei=Naka en-aut-mei=Shuhei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MatsuokaDaiki en-aut-sei=Matsuoka en-aut-mei=Daiki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=GotoKana en-aut-sei=Goto en-aut-mei=Kana kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=MisakiTaro en-aut-sei=Misaki en-aut-mei=Taro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=NagasawaYasuyuki en-aut-sei=Nagasawa en-aut-mei=Yasuyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=ItoSeigo en-aut-sei=Ito en-aut-mei=Seigo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=NomuraRyota en-aut-sei=Nomura en-aut-mei=Ryota kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=NakanoKazuhiko en-aut-sei=Nakano en-aut-mei=Kazuhiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=Matsumoto-NakanoMichiyo en-aut-sei=Matsumoto-Nakano en-aut-mei=Michiyo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= affil-num=1 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=2 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=3 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=4 en-affil=Division of Nephrology, Seirei Hamamatsu General Hospital kn-affil= affil-num=5 en-affil=Department of General Internal Medicine, Hyogo College of Medicine kn-affil= affil-num=6 en-affil=Department of Internal Medicine, Japan Self-Defense Iruma Hospital kn-affil= affil-num=7 en-affil=Department of Pediatric Dentistry, Division of Oral infection and Disease Control, Osaka University Graduate School of Dentistry kn-affil= affil-num=8 en-affil=Department of Pediatric Dentistry, Division of Oral infection and Disease Control, Osaka University Graduate School of Dentistry kn-affil= affil-num=9 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= en-keyword=Streptococcus mutans kn-keyword=Streptococcus mutans en-keyword=collagen-binding protein kn-keyword=collagen-binding protein en-keyword=membrane permeability kn-keyword=membrane permeability en-keyword=cell structure kn-keyword=cell structure en-keyword=RNA-seq kn-keyword=RNA-seq END start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue= article-no= start-page=e13312 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2021 dt-pub=202153 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Roles of Porphyromonas gulae proteases in bacterial and host cell biology en-subtitle= kn-subtitle= en-abstract= kn-abstract=Porphyromonas gulae, an animal-derived periodontal pathogen, expresses several virulence factors, including fimbria, lipopolysaccharide (LPS) and proteases. We previously reported that its invasive efficiency was dependent on fimbriae types. In addition, P. gulae LPS increased inflammatory responses via toll-like receptors. The present study was conducted to investigate the involvement of P. gulae proteases in bacterial and host cell biology. Porphyromonas gulae strains showed an ability to agglutinate mouse erythrocytes and also demonstrated co-aggregation with Actinomyces viscosus, while the protease inhibitors antipain, PMSF, TLCK and leupeptin diminished P. gulae proteolytic activity, resulting in inhibition of haemagglutination and co-aggregation with A. viscosus. In addition, specific proteinase inhibitors were found to reduce bacterial cell growth. Porphyromonas gulae inhibited Ca9-22 cell proliferation in a multiplicity of infection- and time-dependent manner. Additionally, P. gulae-induced decreases in cell contact and adhesion-related proteins were accompanied by a marked change in cell morphology from well spread to rounded. In contrast, inhibition of protease activity prevented degradation of proteins, such as E-cadherin, beta-catenin and focal adhesion kinase, and also blocked inhibition of cell proliferation. Together, these results indicate suppression of the amount of human proteins, such as gamma-globulin, fibrinogen and fibronectin, by P. gulae proteases, suggesting that a novel protease complex contributes to bacterial virulence. en-copyright= kn-copyright= en-aut-name=UrmiAlam Saki en-aut-sei=Urmi en-aut-mei=Alam Saki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=InabaHiroaki en-aut-sei=Inaba en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NomuraRyota en-aut-sei=Nomura en-aut-mei=Ryota kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=YoshidaShoko en-aut-sei=Yoshida en-aut-mei=Shoko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=OharaNaoya en-aut-sei=Ohara en-aut-mei=Naoya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=AsaiFumitoshi en-aut-sei=Asai en-aut-mei=Fumitoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=NakanoKazuhiko en-aut-sei=Nakano en-aut-mei=Kazuhiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=Matsumoto]NakanoMichiyo en-aut-sei=Matsumoto]Nakano en-aut-mei=Michiyo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= affil-num=1 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=2 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=3 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=4 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=5 en-affil=Department of Oral Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and the Advanced Research Center for Oral and Craniofacial Sciences, Dental School, Okayama University kn-affil= affil-num=6 en-affil=Department of Pharmacology, School of Veterinary Medicine Azabu University kn-affil= affil-num=7 en-affil=Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry kn-affil= affil-num=8 en-affil=Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= en-keyword=coaggregation kn-keyword=coaggregation en-keyword=haemagglutination kn-keyword=haemagglutination en-keyword=P. gulae kn-keyword=P. gulae en-keyword=protease kn-keyword=protease en-keyword=protein degradation kn-keyword=protein degradation END start-ver=1.4 cd-journal=joma no-vol=12 cd-vols= no-issue=1 article-no= start-page=1797320 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200804 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Identification and functional analysis of glutamine transporter inStreptococcus mutans en-subtitle= kn-subtitle= en-abstract= kn-abstract=Background
Streptococcus mutans, a biofilm-forming bacterium, possesses several transporters that function as import/export molecules. Among them, the PII protein family is composed of members that regulate glutamine synthesis in bacterial species.
Objective
In this study, we characterized the function of the glutamine transporter in S. mutans MT8148.
Methods
The SMU.732 gene, corresponding to glnP in S. mutans, is homologous to the glutamine transporter gene in Bacillus subtilis. We constructed a glnP-inactivated mutant strain (GEMR) and a complement strain (comp-GEMR) and evaluated their biological functions.
Results
Growth of GEMR was similar in the presence and absence of glutamine, whereas the growth rates of MT8148 and comp-GEMR were significantly lower in the presence of glutamine as compared to its absence. Furthermore, biofilms formed by MT8148 and comp-GEMR were significantly thicker than that formed by GEMR, while the GEMR strain showed a significantly lower survival rate in an acidic environment than the other strains. Addition of n-phenyl-2-naphthylamine, used to label of the membrane, led to increased fluorescence intensity of MT8148 and GEMR, albeit that was significantly lower in the latter.
Conclusions
These results suggest that glnP is associated with glutamine transport in S. mutans, especially the import of glutamine involved in biofilm formation. en-copyright= kn-copyright= en-aut-name=MorikawaYuko en-aut-sei=Morikawa en-aut-mei=Yuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MorimotoSetsuyo en-aut-sei=Morimoto en-aut-mei=Setsuyo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=YoshidaEri en-aut-sei=Yoshida en-aut-mei=Eri kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=NakaShuhei en-aut-sei=Naka en-aut-mei=Shuhei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=InabaHiroaki en-aut-sei=Inaba en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=Matsumoto-NakanoMichiyo en-aut-sei=Matsumoto-Nakano en-aut-mei=Michiyo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= affil-num=1 en-affil=Department of Pediatric Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=2 en-affil=Department of Pediatric Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=3 en-affil=Department of Pediatric Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=4 en-affil=Department of Pediatric Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=5 en-affil=Department of Pediatric Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=6 en-affil=Department of Pediatric Dentistry, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= en-keyword=Streptococcus mutans kn-keyword=Streptococcus mutans en-keyword=glutamine transporter kn-keyword=glutamine transporter en-keyword=biofilm kn-keyword=biofilm en-keyword=membrane protein kn-keyword=membrane protein en-keyword=glnP kn-keyword=glnP END start-ver=1.4 cd-journal=joma no-vol=14 cd-vols= no-issue= article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2014 dt-pub=20140102 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Cross-cultural validity of a dietary questionnaire for studies of dental caries risk in Japanese en-subtitle= kn-subtitle= en-abstract= kn-abstract=Background: Diet is a major modifiable contributing factor in the etiology of dental caries. The purpose of this paper is to examine the reliability and cross-cultural validity of the Japanese version of the Food Frequency Questionnaire to assess dietary intake in relation to dental caries risk in Japanese. Methods: The 38-item Food Frequency Questionnaire, in which Japanese food items were added to increase content validity, was translated into Japanese, and administered to two samples. The first sample comprised 355 pregnant women with mean age of 29.2 +/- 4.2 years for the internal consistency and criterion validity analyses. Factor analysis (principal components with Varimax rotation) was used to determine dimensionality. The dietary cariogenicity score was calculated from the Food Frequency Questionnaire and used for the analyses. Salivary mutans streptococci level was used as a semi-quantitative assessment of dental caries risk and measured by Dentocult SM. Dentocult SM scores were compared with the dietary cariogenicity score computed from the Food Frequency Questionnaire to examine criterion validity, and assessed by Spearman's correlation coefficient (r(s)) and Kruskal-Wallis test. Test-retest reliability of the Food Frequency Questionnaire was assessed with a second sample of 25 adults with mean age of 34.0 +/- 3.0 years by using the intraclass correlation coefficient analysis. Results: The Japanese language version of the Food Frequency Questionnaire showed high test-retest reliability (ICC = 0.70) and good criterion validity assessed by relationship with salivary mutans streptococci levels (r(s) = 0.22; p < 0.001). Factor analysis revealed four subscales that construct the questionnaire (solid sugars, solid and starchy sugars, liquid and semisolid sugars, sticky and slowly dissolving sugars). Internal consistency were low to acceptable (Cronbach's alpha = 0.67 for the total scale, 0.46-0.61 for each subscale). Mean dietary cariogenicity scores were 50.8 +/- 19.5 in the first sample, 47.4 +/- 14.1, and 40.6 +/- 11.3 for the first and second administrations in the second sample. The distribution of Dentocult SM score was 6.8% (score = 0), 34.4% (score = 1), 39.4% (score = 2), and 19.4% (score = 3). Participants with higher scores were more likely to have higher dietary cariogenicity scores (p < 0.001; Kruskal-Wallis test). Conclusions: These results provide the preliminary evidence for the reliability and validity of the Japanese language Food Frequency Questionnaire. en-copyright= kn-copyright= en-aut-name=Shinga-IshiharaChikako en-aut-sei=Shinga-Ishihara en-aut-mei=Chikako kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NakaiYukie en-aut-sei=Nakai en-aut-mei=Yukie kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=MilgromPeter en-aut-sei=Milgrom en-aut-mei=Peter kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=MurakamiKaori en-aut-sei=Murakami en-aut-mei=Kaori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=Matsumoto-NakanoMichiyo en-aut-sei=Matsumoto-Nakano en-aut-mei=Michiyo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Pediat Dent affil-num=2 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Pediat Dent affil-num=3 en-affil= kn-affil=Univ Washington, Dept Oral Hlth Sci affil-num=4 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Pediat Dent affil-num=5 en-affil= kn-affil=Okayama Univ, Grad Sch Med Dent & Pharmaceut Sci, Dept Pediat Dent en-keyword=Food frequency questionnaire kn-keyword=Food frequency questionnaire en-keyword=Cariogenic food kn-keyword=Cariogenic food en-keyword=Diet kn-keyword=Diet en-keyword=Reliability kn-keyword=Reliability en-keyword=Validity kn-keyword=Validity en-keyword=Mutans streptococci kn-keyword=Mutans streptococci END