Did drug resistant genes exist from ancient times?

2017 Fiscal Year Final Research Report

• Project/Area Number: 26650135
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Evolutionary biology
• Research Institution: Juntendo University
• Principal Investigator: Baba Tadashi 順天堂大学, 医学(系)研究科(研究院), 准教授 (30317458)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 復帰抗生物質 / キノロン系抗菌薬 / 自然耐性

Outline of Final Research Achievements

Our resent studies revealed that natural compounds nybomycin are only effective to quinolone-resistant bacteria with mutations in the quinolone-resistant determining regions of their type IIA DNA topoisomerases. We designated such compound as reverse-antibiotic (RA). We have been interested in why nature produces RAs, and hypothesized that there should be many quinolone-resistant, or RA-susceptible bacteria (the targets of RA) in environment. To prove this hypothesis, we screened quinolone-resistant and RA-resistant bacteria from environmental samples, and found that many quinolone resistant bacteria were present in environment. Moreover, we also found that bacterial taxonomic families are strictly categorized into (1) quinolone-resistant and (2) RA-resistant groups. We also found that bacterial families to which human pathogens belong tend to be categorized in (2). This suggests that human pathogens have evolved by chance as quinolone-susceptible, explaining utility of quinolone.

Free Research Field

微生物ゲノム・