Functional and structural analysis of heat-resistant dye-dependent D-lactate dehydrogenase and its application to biosensor devices

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K14394
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 38030:Applied biochemistry-related
• Research Institution: The University of Tokushima (2019-2021); Ritsumeikan University (2018)
• Principal Investigator: HAYSHI Junji 徳島大学, 大学院社会産業理工学研究部(生物資源産業学域), 講師 (20802101)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 酵素工学 / 酵素 / 超好熱菌 / 構造生物学 / FAD

Outline of Final Research Achievements

Dye-dependent dehydrogenase (Dye-DH) has a potential as a biosensor devices.
However, Dye-DH is an unstable enzyme and there are few studies. In this study, we found a large number of dye-dependent D-lactate dehydrogenase (DLDH) in hyperthermophilic bacteria. All DLDHs from hyperthermophilic bacteria showed high thermostable. We succeeded in developing an enzyme electrode on which this high thermostable DLDH is immobilized. Using this electrode, we succeeded in detecting D-lactic acid in food samples. This study is considered to play an important role in the development of new measurement methods for D-lactic acid. We also succeeded in analyzing the X-ray crystal structure of DLDH.

Free Research Field

酵素工学

Academic Significance and Societal Importance of the Research Achievements

Dye-DHは不安定な酵素であり、有用性に反して研究例が少ない。そのため応用例は限定的であり、また酵素の機能改良に必須の構造情報も少ない。本研究により開発に成功したD-乳酸測定用バイオセンサーは、D-乳酸に対して特異的で、且つ長期間利用できることが明らかとなった。D-乳酸は診断用バイオマーカーや食品の品質管理の指標として有用であるが、これまでに簡便に測定する方法は無かった。本研究の成果はD-乳酸の新規測定法開発において重要な役割を果たすと考えられる。また、Dye-DHの構造情報の取得によりDye-DHの機能改良も可能となり、高性能センサーや電極の開発にも繋がる成果を得たといえる。