Analysis of stress response mechanism in biofilm formation of S. mutans.

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K20590
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Orthodontics/Pediatric dentistry
• Research Institution: Okayama University
• Principal Investigator: Yasokawa Yuki (松三友紀) 岡山大学, 大学病院, 助教 (90732800)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: Streptococcus mutans / バイオフィルム / プロテオーム

Outline of Final Research Achievements

Streptococcus mutans, implicated as a primary causative agent of dental caries, shows acid tolerance as an important characteristic and is known to survive under acidic conditions, while the molecular chaperone DnaK has been suggested to be involved in its acid-tolerance mechanism. For this study, S. mutans strains with overexpression (DnaK-o) and suppressed expression (DnaK-s) of DnaK were constructed and examined. The acid tolerance of DnaK-o was obviously elevated as compared to the parental and DnaK-s strains. In addition, DnaK-o showed strong cell aggregation under acidic conditions. The structure of biofilms formed by DnaK-s was sparse as compared to biofilms formed by the other strains, while formed by DnaK-o had significantly greater height. These results suggest that DnaK expression by S. mutans may have effects on the structure of biofilm formed by the organism, indicating the importance of control of cell surface protein expression in regard to the biofilm formation.

Free Research Field

小児歯科学分野