The mechanism for biofilm formation in periodontal pathogen, Prevotella intermedia.

• Project/Area Number: 17K19769
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Oral Science and related fields
• Research Institution: Nagasaki University
• Principal Investigator: NAITO Mariko 長崎大学, 医歯薬学総合研究科(歯学系), 准教授 (20244072)
• Research Collaborator: SHOJI Mikio ; SATO Keiko ; YUKITAKE Hideharu
• Project Period (FY): 2017-06-30 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥6,500,000 (Direct Cost: ¥5,000,000、Indirect Cost: ¥1,500,000); Fiscal Year 2018: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000); Fiscal Year 2017: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000)
• Keywords: 口腔細菌学 / 歯周病原菌 / バイオフィルム / 遺伝子操作 / 感染症 / 歯学 / 微生物 / プロテオーム

Outline of Final Research Achievements

Biofilm formation is one of virulence factor of periodontal pathogen, Prevotella intermedia. Our previous study suggested that the Type IX secretion system (T9SS) might translocate the essential component for biofilm formation. Here we searched all genes of P. intermedia by conserved motif sequence for T9SS-translocated protein, then defined 6 candidate genes. By our established site-directed mutagenesis procedure, we succeed to generate 5 mutants. Two of those mutants showed the significant reduced biofilm formation. It indicated that those 2 genes have the essential role for biofilm formation in P. intermedia.

Academic Significance and Societal Importance of the Research Achievements

プレボテラ・インターメディアはグラム陰性偏性嫌気性細菌であり、慢性歯周炎の主要病原細菌の一つとしてあげられる。さらに、急性壊死性潰瘍性歯肉炎、妊娠性思春期性歯肉炎などの発症と強い関連が報告されている。本研究の成果は世界に先駆けて本菌の重要な病原因子であるバイオフィルム形成に関わる遺伝子を２つ同定することができたことである。この成果は今後の本菌の病原性機構の詳細な解明に役立つと考える。

Research Products

• [Journal Article] PGN_0297 is an essential component of the type IX secretion system (T9SS) in Porphyromonas gingivalis: Tn-seq analysis for exhaustive identification of T9SS-related genes. (2019)
  • Author(s): Naito M, Tominaga T, Shoji M, Nakayama K.
  • Journal Title: Microbiol Immunol. Volume: 63(1) Issue: 1 Pages: 11-20
  • DOI: 10.1111/1348-0421.12665
  • Peer Reviewed / Open Access
• [Journal Article] Identification of genes encoding glycosyltransferases involved in lipopolysaccharide synthesis in Porphyromonas gingivalis. (2018)
  • Author(s): Shoji M, Sato K, Yukitake H, Kamaguchi A, Sasaki Y, Naito M, Nakayama K.
  • Journal Title: Mol Oral Microbiol. Volume: 33(1) Issue: 1 Pages: 68-80
  • DOI: 10.1111/omi.12200
  • Peer Reviewed / Open Access
• [Journal Article] Immunoglobulin-like domains of the cargo proteins are essential for protein stability during secretion by the type IX secretion system. (2018)
  • Author(s): Sato K, Kakuda S, Yukitake H, Kondo Y, Shoji M, Takebe K, Narita Y, Naito M, Nakane D, Abiko Y, Hiratsuka K, Suzuki M, Nakayama K.
  • Journal Title: Mol Microbiol. Volume: 110(1) Issue: 1 Pages: 64-81
  • DOI: 10.1111/mmi.14083
  • Peer Reviewed
• [Journal Article] Rab44, a novel large Rab GTPase, negatively regulates osteoclast differentiation by modulating intracellular calcium levels followed by NFATc1 activation. (2018)
  • Author(s): Yu Yamaguchi, Eiko Sakai, Kuniaki Okamoto, Hiroshi Kajiya, Koji Okabe, Mariko Naito, Tomoko Kadowaki and Tsukuba T
  • Journal Title: Cell Mol Life Sci. Volume: 75 Issue: 1 Pages: 33-48
  • DOI: 10.1007/s00018-017-2607-9
  • Peer Reviewed / Open Access
• [Presentation] Prevotella intermedia のIX 型分泌シグナル保有タンパク質分解酵素の解析 (2018)
  • Author(s): 内藤真理子，中山浩次
  • Organizer: 第91回日本細菌学会総会
• [Presentation] Prevotella intermediaのIX型分泌シグナル保有タンパク質分解酵素の解析 (2018)
  • Author(s): 内藤真理子，中山浩次
  • Organizer: 第91回日本細菌学会総会
• [Presentation] 高密度Tn-seq法によるIX型分泌機構関連遺伝子の探索 (2017)
  • Author(s): 内藤真理子，庄子幹郎，中山浩次
  • Organizer: 第70回日本細菌学会九州支部総会・第54回日本ウイルス学会九州支部総会
• [Presentation] Porphyromonas gingivalis LPSの生合成に関わる4つの糖転移酵素遺伝子の発見 (2017)
  • Author(s): 庄子幹郎, 佐藤啓子, 雪竹英治, 内藤真理子, 中山浩次
  • Organizer: 第59回歯科基礎医学会学術大会