Research related to invasive infection of CA-MRSA-ST8-SCCmecIVl derived from diabetic patient

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K08777
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Bacteriology (including mycology)
• Research Institution: National Institute of Infectious Diseases (2018); Hiroshima University (2016-2017)
• Principal Investigator: Sugai Motoyuki 国立感染症研究所, 薬剤耐性研究センター, センター長 (10201568)
• Co-Investigator(Kenkyū-buntansha): 久恒 順三 国立感染症研究所, 薬剤耐性研究センター, 主任研究官 (40513180)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: CA-MRSA / ST8 / TSST-1

Outline of Final Research Achievements

We investigated the detection rate of the skin infection isolated CA-MRSA-ST8-SCCmecIVl clone used by PCR genotyping. Over 560 strains isolated from skin infection, ST8 clone was detected 22.7% by the decubitus, open pus and unopen pus, especially decubitus and open pus. Detection rate of ST8-SCCmecIVl was 4.8% on 560 strains, 21.3% on ST8 group. We investigated that comparative analysis of TSST1 positive ST5 and ST8 used by RNA-Seq, because of TSST-1 production control of ST8-SCCmecIVl clone clearly. As a result, tst1 gene expression of ST8-SCCmecIVl clone was significantly increased than TSST1 positive ST5 clone. Gene expression of agr operon was extremely high in ST8-SCCmecIVl clone, as well as transcriptional regulator genes under agr operon control.

Free Research Field

細菌学

Academic Significance and Societal Importance of the Research Achievements

本研究で得られた研究成果は、近年増加傾向にある全身播種性CA-MRSA感染症、特に、日本固有に分離されるCA-MRSA-ST8-SCCmecIVl クローンのゲノム構造の特徴性から、疫学解析と病原因子の比較解析から病態形成機構が分子レベルでの究明につながるものである。これにより、侵襲性MRSA感染症の予防及び治療戦略の情報を基礎から臨床へのフィードバックできる極めて重要な研究であると位置付けている。