Abstract
The cultivation and genetic manipulation of Treponema denticola, a Gram-negative oral spirochaeta associated with periodontal diseases, is still challenging. In this study, we formulated a simple medium based on a commercially available one, and established a transformation method with high efficiency. We then analyzed proteins in a membrane fraction in T. denticola and identified 16 major membrane-associated proteins, and characterized one of them, TDE2508, whose biological function was not yet known. Although this protein, which exhibited a complex conformation, was presumably localized in the outer membrane, we did not find conclusive evidence that it was exposed on the cell surface. Intriguingly, a TDE2508-deficient mutant exhibited significantly increased biofilm formation and adherent activity on human gingival epithelial cells. However, the protein deficiency did not alter autoaggregation, coaggregation with Porphyromonas gingivalis, hemagglutination, cell surface hydrophobicity, motility, or expression of Msp which was reported to be an adherent molecule in this bacteria. In conclusion, the major membrane protein TDE2508 regulates biofilm formation and the adhesive potency of T. denticola, although the underlying mechanism remains unclear.
Highlights
Treponema denticola is a Gram-negative anaerobe that is classified as a spirochaete and has periplasmic flagella, which confer motility to enable the bacterium to move in a semisolid medium [1]
Ruby et al showed that T. denticola grew in a relatively simple medium consisting of brain-heart infusion broth and some supplements, which called Modified NOS [23]
We tried Modified GAM, which is widely used in Japan as a general medium for cultivation of anaerobic bacteria
Summary
Treponema denticola is a Gram-negative anaerobe that is classified as a spirochaete and has periplasmic flagella, which confer motility to enable the bacterium to move in a semisolid medium [1]. The virulence factors of T. denticola have been reported and are summarized in reviews [1,5,6]. Msp (named from major sheath protein), the most abundant protein in the bacteria, acts as an adherent factor to bacteria and host tissues [7,8]. It has reported to function as a porin [9,10]. The chymotrypsin-like protease dentilisin is a major virulence molecule in this pathogen [14,15]. It is reported that dentilisin functions as an adherent molecule to other oral bacteria [16] and host molecules [17]. We found that T. denticola grew well in a medium that was formulated based on a commercially-available medium, and we established a highly efficient method for genetic modification
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
