[WCB] 【共催】細菌学若手コロッセウム―未来を拓く若手細菌学研究―

[WCB-9] マダニ由来抗菌ペプチドへの耐性機構に関連した遺伝子の同定

下田 蒼¹，伊藤 隼哉²，仲川 清隆²，安藤 太助¹，米山 裕¹ (¹東北大院・農・動物微生物，²東北大院・農・機能分子解析)

Antimicrobial resistance (AMR) is very serious problem in the world. Therefore, development of novel antimicrobial agents to overcome AMR is urgently required. Persulcatusin (IP), an antimicrobial peptide from hard tick (Ixodes persulcatus), exhibits potent antimicrobial activity against Gram-positive bacteria such as Staphylococcus aureus. We have focused on IP as promising compound for AMR because IP also exhibits antimicrobial activity against AMR bacteria such as methicillin-resistant S. aureus (MRSA) and vancomycin-resistant S. aureus (VRSA). In this study, to identify the genes associated with resistance to IP, we performed screening of hyper-susceptible mutants using the Nebraska Transposon Mutant Library with approximately 2,000 transposon mutants. We found that 16 mutant strains showed hyper-susceptibility to IP. The disrupted genes identified were associated with resistance to antibiotics including cationic antimicrobial peptides, Nisin (lantibiotics from L. lactis), and vancomycin. It is therefore suggested that resistance mechanism of IP has a crosstalk with that of cell-wall biosynthesis inhibitor via binding to cell-wall precursor. Therefore, IP might have another unknown activity like inhibition of cell-wall biosynthesis.