Research for highly virulent Helicobacter pylori in East Asia with next-generation sequencing technologies

2016 Fiscal Year Final Research Report

• Project/Area Number: 15H06404
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Gastroenterology
• Research Institution: Kobe University
• Principal Investigator: Akira Iwamoto 神戸大学, 医学研究科, 医学研究員 (10757347)
• Research Collaborator: Azuma Takeshi ; Tanahashi Toshihito ; Okada Rina
• Project Period (FY): 2015-08-28 – 2017-03-31
• Keywords: ヘリコバクターピロリ菌 / CagA

Outline of Final Research Achievements

Helicobacter pylori CagA is known to have oncogenic activity, and the CagA C-terminal region carries the amino acid motif Glu-Pro-Ile-Tyr-Ala (EPIYA), which occurs as two major subtypes. Using whole-genome sequencing (WGS), we examined H. pylori cagA full sequences and analyzed single nucleotide variants (SNVs) and amino acid changes (AACs) related to CagA. Clinical H. pylori isolates from 24 patients. Twenty strains with EPIYA-D and 4 strains with non EPIYA-D were subjected to WGS. Using ATCC26695 as a reference, there were 57 highly frequent SNVs and 36 AACs in 20 strains with EPIYA-D. Eighteen of these 36 AACs (50%) were found in Domain II, which is located in the core of the N-terminal region that binds to the acidic inner leaflet of host epithelial cell membrane. Two AACs, Ile1065Thr and Thr1151Met, were observed in all 20 isolates with EPIYA-D. Notably, Ile1065Thr occurred regardless of whether the EPIYA-D or non-EPIYA-D motif was present.

Free Research Field

消化器内科学