The role of unculturable bacteria as sources of antibiotic resistance genes

• Project/Area Number: 17K19246
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Agricultural chemistry and related fields
• Research Institution: Rakuno Gakuen University
• Principal Investigator: Usui Masaru 酪農学園大学, 獣医学群, 准教授 (60639540)
• Project Period (FY): 2017-06-30 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥6,370,000 (Direct Cost: ¥4,900,000、Indirect Cost: ¥1,470,000); Fiscal Year 2018: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000); Fiscal Year 2017: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
• Keywords: 難培養細菌 / 薬剤耐性 / 難培養

Outline of Final Research Achievements

To isolate unculturable bacteria, we used the starved nutrient agar. Several environmental samples were applied to isolate unculturable bacteria. In results, 103 types of unculturable bacteria were isolated. Twenty-nine of the isolates were novel species. Some of these 29 strains were resistant to cephalosporins and tetracyclines. These result suggest that these unculturable bacteria were reservoir of antibiotic resistance.

Academic Significance and Societal Importance of the Research Achievements

今回、29種類の新規微生物が同定できた。また、これらの株のいくつかは多数の抗生物質に対して耐性を示した。これまでのところ、これらの株から薬剤耐性遺伝子は見つかっていないが、今後の解析により、薬剤耐性遺伝子が見つかる可能性は高い。これらの結果により、環境中の難培養細菌が薬剤耐性遺伝子のレゼルボアとなっている可能性が示される。本研究は、環境中の実態を解明につながり、今後の薬剤耐性問題に対する対策につなげることが期待される。