Mechanism of thiamin transport in Helicobacter pylori providing a basis for complementary therapy for the infection.

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K08053
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental and hygienic pharmacy
• Research Institution: Mukogawa Women's University
• Principal Investigator: Nosaka Kazuto 武庫川女子大学, 薬学部, 教授 (10228314)
• Co-Investigator(Renkei-kenkyūsha): KONNO Hiroyuki 山形大学, 理工学研究科, 教授 (50325247)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: ヘリコバクター・ピロリ / チアミン / トランスポーター / PnuT / 感染

Outline of Final Research Achievements

Helicobacter pylori lacks the genes involved in the de novo synthesis of thiamin, and therefore is a thiamin auxotroph. In this study, we found that thiamin is incorporated into H. pylori SS1 strain via a facilitated diffusion with an apparent Km value of 19 μM, and that the transport system seems to recognize the pyrimidine moiety of thiamin. In addition, when the pnuT gene was expressed in a thiamin transport-deficient Escherichia coli strain, the transport activity with a Km value of 3.5 μM was restored. Further, the pnuT-deficient H. pylori strain exhibited reducing thiamin transport activity to less than 20% of the wild-type strain, and required 100 times more thiamin than the wild-type strain to achieve growth equal to that of the wild-type. These findings reflect the presence of multiple routes for entry of thiamin into H. pylori, and it is likely that PnuT is responsible for the high affinity thiamin transport and serves as target for antimicrobial agent for H. pylori.

Free Research Field

環境・衛生系薬学、代謝生化学