Intrasurvival methanism of Escherichia albertii in Acanthamoeba

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K07498
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 49050:Bacteriology-related
• Research Institution: Kagoshima University
• Principal Investigator: Ooka Tadasuke 鹿児島大学, 医歯学域医学系, 准教授 (50363594)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: Escherichia albertii / アメーバ内増殖機構 / 菌濃縮法 / タイピング / 病原性

Outline of Final Research Achievements

Escherichia albertii is a recently recognized human enteropathogen. In this study, we performed the functional analysis to identify the mechanism of intracellular-survival in Acanthamoeba castellanii of this species and also the virulence mechanism in mammalian cells. In addition, we tried to develop effective methods to identify the source of infection and to perform the survey of prevalence of this species in the environment.
The results revealed that 1)EACBF1370 protein is important for intracellular survival in A. castellanii, 2)we identified the E. albertii-specific surface factor and developed the immunomagnetic beads-based concentration and enrichment method for this species, 3)the fliC genes of E. albertii were grouped into four clearly distinguishable types designated E. albertii H-genotypes (EAHg1-EAHg4).

Free Research Field

細菌学

Academic Significance and Societal Importance of the Research Achievements

本研究では、集団感染の起因菌となっている新興下痢症起因菌E. albertii (EA)について、ゲノム情報および先行研究の知見を基に解析を進め、本菌の環境（特に水環境）中での生態に関する情報を得ることができ、本菌の感染経路を推定する上での有用な知見を得ることが出来た。また、本菌による感染事例では、感染源に存在する菌数が少ないためかその同定に至る例が少ないことが問題であるが、本研究において、EAの表層分子を利用した菌濃縮法および菌タイピング法を開発し、その有用性も明らかに出来たことで、今後の迅速な感染源同定などに繋がることが期待される。