Research on the relationship between psm-mec mutations and MRSA virulence

2019 Fiscal Year Final Research Report

• Project/Area Number: 15H05279
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Bacteriology (including mycology)
• Research Institution: Okayama University (2017-2019); The University of Tokyo (2015-2016)
• Principal Investigator: Kaito Chikara 岡山大学, 医歯薬学総合研究科, 教授 (60420238)
• Co-Investigator(Kenkyū-buntansha): 松本 靖彦 東京大学, 薬学研究科(研究院), 助教 (60508141)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: psm-mec / MRSA / 毒素

Outline of Final Research Achievements

In MRSA isolates in Japan, strains carrying psm-mec gene mutations produce higher amounts of toxins than those carrying intact psm-mec gene. However, it is not known whether this theory is applicable to other MRSA strains having different genetic backgrounds from the MRSA isolates in Japan. In this study, we isolated MRSA strains from north and center regions of Thailand and revealed that strains carrying psm-mec mutations produce higher amounts of toxins than those carrying intact psm-mec. In addition, the MRSA isolates in Thailand had different genetic backgrounds from the MRSA isolates in Japan. These results suggest that psm-mec mutations cause high toxin production in MRSA isolates having various genetic backgrounds.

Free Research Field

分子生物学

Academic Significance and Societal Importance of the Research Achievements

メチシリン耐性黄色ブドウ球菌（MRSA）は世界規模で流行する病原性細菌であり、新しい治療法と予防法の確立が急務である。本研究では、海外で流行するMRSAにおいて、psm-mec遺伝子の変異の有無が毒素産生量と対応していることを見出した。本研究結果は、psm-mecの変異の有無を検出することが、患者から分離されたMRSA株の危険度を判定する上で有効であることを示唆している。