Repression of the spread of antimicrobial resistant bacteria using the bacterial toxin-antitoxin system

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K07493
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 49050:Bacteriology-related
• Research Institution: Saitama University
• Principal Investigator: Otsuka Yuichi 埼玉大学, 理工学研究科, 准教授 (10548861)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: トキシン-アンチトキシン系 / 細菌 / ファージ / 水平伝播 / 形質転換 / 形質導入

Outline of Final Research Achievements

In recent years, the spread of drug-resistant bacteria has become a serious social problem, and a solution to this problem is urgently needed. In addition to the proliferation of resistant bacteria, horizontal gene transfer, in which genes or mutations that confer resistance to a drug are taken up by other bacteria, is a cause in the spread of resistant bacteria. Transduction, transformation, and conjugation are known as mechanisms that lead to the horizontal gene transfer. In this study, we found that the bacterial toxin-antitoxin system (TA) which is a genetic module composed of a toxin and its cognate antitoxin, inhibits the induction of lysogenic phages during the transduction process. We also found that the TA system suppressed the transformation of plasmid DNA. These results indicate that the TA system can function as a mechanism to suppress the horizontal gene transfer.

Free Research Field

分子微生物学

Academic Significance and Societal Importance of the Research Achievements

近年、薬剤耐性菌（以下, 耐性菌）の拡大が深刻な社会問題となり、その対策が急務になっている。耐性菌が増殖することに加えて、薬剤に耐性を与える遺伝子や変異が他の菌に取り込まれる水平伝播が、耐性菌拡大の要因である。水平伝播をおこすしくみとして形質導入、形質転換、および接合が知られている。本研究では、細菌がもつトキシン-アンチトキシン系（以下, TA）が形質導入と形質転換を抑えることを見出した。今後、TAを活性化するしくみや物質を発見できれば、薬剤耐性菌の蔓延を抑える対策に応用できる可能性がある。また、本研究はTAの新たな役割を明らかにしたことにもなり、細菌学分野の進展にも貢献すると考える。