Cyanide sensitivity in direct electron transfer-type bioelectrocatalysis by membrane-bound alcohol dehydrogenase from Gluconobacter oxydans

Taiki Adachi; Keisei Sowa; Yuki Kitazumi; Osamu Shirai; Kenji Kano

doi:10.1016/j.bioelechem.2021.107992

Cyanide sensitivity in direct electron transfer-type bioelectrocatalysis by membrane-bound alcohol dehydrogenase from Gluconobacter oxydans

Bioelectrochemistry. 2022 Feb:143:107992. doi: 10.1016/j.bioelechem.2021.107992. Epub 2021 Oct 30.

Authors

Taiki Adachi¹, Keisei Sowa¹, Yuki Kitazumi², Osamu Shirai¹, Kenji Kano³

Affiliations

¹ Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan.
² Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan. Electronic address: kitazumi.yuki.7u@kyoto-u.ac.jp.
³ Office of Society Academia Collaboration for Innovation, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.

PMID: 34773823
DOI: 10.1016/j.bioelechem.2021.107992

Abstract

An overexpression system of membrane-bound alcohol dehydrogenase (ADH) from Gluconobacter oxydans was constructed to examine its bioelectrocatalytic characteristics. The effects of cyanide (CN^-) addition on the kinetics of direct electron transfer (DET)-type bioelectrocatalysis by ADH were analyzed. CN^- enhanced the bioelectrocatalytic activity, while the catalytic activity in the solution remained unchanged, even in the presence of CN^-. Electrochemical methods and electron spin resonance spectroscopy showed the detailed electron transfer pathway in the DET-type bioelectrocatalysis by ADH. Briefly, ADH is suggested to communicate with an electrode via a CN^--insensitive and H⁺-sensitive heme c in DET. These characteristics of ADH with respect to CN^- suggest the involvement of ADH in CN^--insensitive respiration in G. oxydans.

Keywords: Direct electron transfer; Electron transfer pathway; Hemoprotein; Redox enzyme.

MeSH terms

Gluconobacter oxydans*