Project description:Background: Treponema denticola is strongly associated with the development of periodontal disease. Both synergistic and antagonistic effects are observed among bacterial species in the process of biofilm formation. Bacteriocin-related genes have not yet been fully characterized in periodontopathic bacteria. The aim of this study was to detect and characterize bacteriocin-associated proteins in T. denticola. Methods: The whole genome sequence of T. denticola ATCC 35405 was screened with a Streptococcus mutans bacteriocin immunity protein (ImmA/Bip) sequence. The prevalence of homologous genes in T. denticola strains was then investigated by Southern blotting. Expression of the genes was evaluated by qRT-PCR. Results: In the genome sequence of T. denticola, an amino acid sequence coded by open reading frame TDE_0719 showed 26% identity with the S. mutans ImmA. Furthermore, two protein sequences coded by TDE_0425 and TDE_2431 in T. denticola ATCC 35405 showed ~40% identity with that coded by TDE0719. Therefore, TDE_0425, TDE_0719, and TDE_2431 were designated as tepA1, A2, and A3, respectively. Open reading frames showing similarity to the HlyD family of secretion proteins were detected downstream of tepA1, A2, and A3. They were designated as tepB1, B2, and B3, respectively. A gene harboring a bacteriocin-like signal sequence was detected upstream of tepA1. The prevalence of tepA1 and A2 differed among Treponema species. Susceptibility to chloramphenicol and ofloxiacin was slightly decreased in a tepA2 mutant while that to kanamycin was increased. Expression of tepA3-B3 was increased in the tepA2 mutant. Conclusion: These results indicate that T. denticola ATCC 35405 has three potential bacteriocin export proteins and that the presence of these genes differs among the Treponema strains. These proteins may be involved in resistance to chloramphenicol.
Project description:Porphyromonas gingivalis and Treponema denticola are periodontalpathogens that are associated with the severity and progression of periodontal diseases. This study investigates the gene expression of Porphyromonas gingivalis during co-culture with Treponema denticola
Project description:Porphyromonas gingivalis and Treponema denticola are periodontalpathogens that are associated with the severity and progression of periodontal diseases. this study investigates the gene expression of Treponema denticola during co-culture with Porphyromonas gingivalis.
Project description:Treponema denticola is involved in chronic periodontitis pathogenesis. The mechanism underlying the regulation of the expression of its virulence factors, such as major surface protein (Msp) is yet to be clarified. We determined the gene expression profiles of Msp-deficient mutants of T. denticola. Gene expression profiles of T. denticola ATCC 35405 (wild type), and msp-deficient mutant, DMSP3, were determined using DNA microarray analysis. In addition to several differentially expressed genes, dentilisin expression was reduced in DMSP3. Potential repressor, TDE_0344, was elevated in DMSP3.
Project description:Treponema denticola is a major pathogen in periodontal disease, frequently isolated from lesions of chronic periodontitis. The ability to adopt its environment is believed to be important for T. denticola in colonizing and proliferating in the gingival crevice. T. denticola use serum as a major nutrient source in the gingival crevices, suggesting that this microorganism utilize serum components to proliferate in gingival crevice. The purpose of this study was to identify T. denticola serum utilization genes. Precultured T. denticola were suspended in tryptone-yeast extract-gelatin-volatile fatty acids medium containing 0, 1 and 10% serum, and incubated anaerobically for 17 h. Total RNA was isolated and T. denticola gene expression was compared by microarray and reverse transcription-polymerase chain reaction. In serum-depleted conditions, the expression of a potential hydroxylamine reductase, several ABC transporters, and phosphoenolpyruvate synthase were increased, while methyl-accepting chemotaxis proteins and a transcriptional regulator were decreased. The results suggest that T. denticola may uptake serum components via ABC transporters. Decreased dmcA expression with decreased serum concentration suggests its involvement in chemotaxis toward serum-rich environments.
Project description:The objectives of this investigation were to examine changes in the host transcriptional profiles during a Treponema denticola infection using a murine calvarial model of inflammation and bone resorption. T. denticola ATCC 35404 was injected into the subcutaneous soft tissue over the calvaria of BALB/c mice for 3 days, after which the soft tissues and calvarial bones were excised. RNA was isolated from infected soft tissues and calvarial bones and analyzed for transcript profiles using Murine GeneChip® MG-MOE430A Affymetrix arrays to provide a molecular profile of the events that occur following infection of these tissues. We used mouse microarrays to detail the molecular profile of the events that occur following infection of calvarial and bone tissues and identified distinct classes of up- and down-regulated genes during this process.
Project description:Treponema denticola is a major etiological agent of chronic periodontis. Dentipain is one of the virulence factors of this microorganism. The localization and function of the protein has yet to be clarified although it has shown to be involved in the virulence of T. denticola. Therefore, this study aimed to characterize the role of dentipain in T. denticola. To investigate the function of dentipain, dentipain deficient mutant was constructed using an ermFermAM cassette and gene expression profile of the mutant was evaluated by microarray analysis. Growth rate of the dentipain-deficient mutants was smaller than that of the wild-type strain. In the mutant. Thirty-five genes in differentially expressed genes by the microarray analysis annotated as membrane or plasma membrane in gene ontology. Hydrophobicity of the mutant were higher than that of the wild-type strain. These findings suggest that dentipain involved in the surface characteristics and growth of T. denticola.
Project description:The objectives of this investigation were to examine changes in the host transcriptional profiles during a Treponema denticola infection using a murine calvarial model of inflammation and bone resorption. T. denticola ATCC 35404 was injected into the subcutaneous soft tissue over the calvaria of BALB/c mice for 3 days, after which the soft tissues and calvarial bones were excised. RNA was isolated from infected soft tissues and calvarial bones and analyzed for transcript profiles using Murine GeneChip® MG-MOE430A Affymetrix arrays to provide a molecular profile of the events that occur following infection of these tissues. We used mouse microarrays to detail the molecular profile of the events that occur following infection of calvarial and bone tissues and identified distinct classes of up- and down-regulated genes during this process. T. denticola was injected at 1.5 x 109 (N = 10) into the soft tissues overlying the calvaria of the mice for 3 days. A control group (N = 9) was injected with vehicle once daily for 3 days. Mice were euthanized 8 h after the last injection. The calvarial bones and overlying soft tissues from 5 mice in each group were excised, snap frozen in liquid nitrogen, and stored at –80°C until RNA isolation. Total RNA was isolated from the frozen calvarial tissue and calvarial bone from each mouse (T. denticola infected and control animals) with Trizol reagent (Invitrogen, CA). Equal amounts of RNA from samples were labeled and hybridized on a mouse GeneChip following the protocol described in the GeneChip Expression Analysis Technical manual (Affymetrix, Santa Clara, CA). After hybridization, the GeneChip arrays were stained and scanned in an Affymetrix GCS 3000 7G Scanner.
Project description:Treponema denticola is a major etiologic agent of chronic periodontitis. On the outer sheath of T. denticola, several proteins such as the major outer sheath protein were detected, and among them, a 95 kDa protein has not yet been characterized. The aim of this study was to characterize the function of this 95 kDa protein. A gene encoding this 95 kDa protein (TDE_1072) of T. denticola was inactivated by homologous recombination. We compared growth curves between the TDE_1072 mutant and wild-type strains as well as differences in gene expression by DNA microarray analysis. Differentially expressed genes identified by microarray analysis were confirmed by quantitative reverse transcription-polymerase chain reaction. The proteins encoded by TDE_1072, TDE_1073, TDE_1074, TDE_1075, and TDE_1076 shared respective similarities to the substrate-binding domain (DppA) of an ABC-type dipeptide/oligopeptide/nickel transport system, and to the permease component (DppB and DppC) and ATPase component (DppD and DppF) of an ABC-type dipeptide/oligopeptide/nickel transport system. Inactivation of dppA attenuated the growth of T. denticola and down-regulated expression of dppB-dppF. In contrast, expression of oppB-oppF was upregulated in the mutant. Our findings indicate that TDE_1072 may be a potential periplasmic solute binding protein encoded by dppA that is involved in the organization of a peptide uptake system with dppB-dppF.