Analysis of the roll of 3 types of cytolethal distending toxin in Campylobacter fetus

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K16247
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 49050:Bacteriology-related
• Research Institution: Osaka Metropolitan University (2022-2023); Osaka Prefecture University (2020-2021)
• Principal Investigator: Hatanaka Noritoshi 大阪公立大学, 大学院獣医学研究科, 准教授 (20803745)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: Campylobacter / 細胞膨化致死毒素

Outline of Final Research Achievements

Campylobacter fetus is considered a zoonoticsis pathogen. Cytolethal distending toxin (CDT) is one of the well-characterized virulence factors in Campylobacter. To understand how these three CDTs relate to the pathogenicity of C. fetus, we attempt to analyze the distribution of three CDT-encoding cdt gene clusters and the variation in CDT production of 140 strains. Interestingly, when we attempt to detect cdt gene clusters, all three cdt gene clusters were detected from all tested strains. Further, to analyze the sequence of these genes and sequence type (ST), whole-genome sequencing was carried out with 38 different pulse-field gel electrophoresis (PFGE) types of C. fetusstrains. Thirty-eight isolates were characterized with six STs and each cdt gene cluster sequence showed close similaritywere conserved. Sequence variations in each cdt gene cluster were ST dependent, and the deletion and insertion resulted in the truncated amino acid sequence of different CDT subunits.

Free Research Field

細菌学

Academic Significance and Societal Importance of the Research Achievements

本研究ではCampylobacter fetusにおいてなぜ本菌種が3種類の細胞膨化致死毒素(CDT)の遺伝子を保有しているのかを検討した。3種類のCDTのうち2種類のCDTに生物活性があることが明らかとなり、かつ細胞指向性も異なることを明らかとした。本成果は、C. fetusがなぜ動物とヒトの両方で疾患を引き起こし、かつ他のカンピロバクター属菌と異なり腸管外感染症を引き起こすのかについてさらなる検討が可能となった。