Development of a novel antimicrobial method targeting conjugation systems of drug-resistant plasmid

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K08455
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 54030:Infectious disease medicine-related
• Research Institution: Chugoku Gakuen University (2019-2020); Kawasaki Medical School (2018)
• Principal Investigator: Kawano Mitsuoki 中国学園大学, 公私立大学の部局等, 准教授(移行) (00455338)
• Co-Investigator(Kenkyū-buntansha): 小椋 義俊 久留米大学, 医学部, 教授 (40363585)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 薬剤耐性菌 / バクテリオファージ / ファージセラピー / アンチセンスRNA / 遺伝子発現制御法 / 抗菌法 / 感染制御法 / 性線毛

Outline of Final Research Achievements

In this study, I carried out basic technology development of a novel phage therapy using a M13 phage-based genetic engineered phagemid, which combines characteristics of both phage and plasmid, to specifically target F-pili producing bacteria. This approach suppresses expression of essential genes in bacteria by antisense RNAs transcribed from the phagemid. Growth inhibited phenotypes were facilitated in hfq- conditions. Phage lysates were prepared from cells harboring phagemids as a lethal-agent delivery tool. Targeting the rpsM ribosome protein coding gene by phagemid-derived M13 phage infection of E. coli containing a carbapenem-producing F-plasmid and multidrug-resistant Klebsiella pneumoniae containing an F plasmid resulted in the death of over 99.99% of infected bacteria. This study provides a possible strategy for treating bacterial infection and can be applied to any F-pilus producing bacterial species.

Free Research Field

細菌感染症学

Academic Significance and Societal Importance of the Research Achievements

畜産現場における抗菌薬の乱用が薬剤耐性菌を産生する主要な原因になっているが、ファージを用いた新規抗菌法は、代替法として畜産分野での実用化が期待できる。また、性線毛を産生するサルモネラ属菌や腸管出血性大腸菌O157などの食中毒菌を人に感染する前に食品や環境中から除菌する方法の開発につながる。さらに、水平伝播による薬剤耐性遺伝子の拡散防止や、新規薬剤耐性遺伝子による薬剤耐性菌の出現を遅らせることができ公衆衛生的な問題に貢献できる。これらは、医療費を含む社会的・経済的負担の大幅な軽減にもつながると考えられる。