Discover a new ion pump working with light, stability is world record

March 14(Tue), 2017

Kanae Kanehara, a Sophomore Undergraduate at Faculty of Pharmaceutical Sciences, Okayama University, Yuki Sudo, Professor at Division of Pharmaceutical Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Takashi Tsukamoto, Assistant Professor at the division, and Susumu Yoshizawa, Associate Professor at Atmosphere and Ocean Research Institute, The University of Tokyo have discovered a membrane protein, rhodopsin RxR, derived from a eubacterium.  Functional analysis revealed that RxR is the world’s most stable light-driven ion pump.


The world’s most stable rhodopsin was the rhodopsin TR, found by this research group in 2013 from a hot spring in the U.S., stable for up to 37.5 minutes after heat treatment.  RxR is stable for up to 600 minutes, about 16 times the world record.


This study was reported in the U.K.’s international journal Scientific Reports on March 14.


This discovery would lead to large-amount production and analysis of ion transporters, which are generally known to be unstable.  The rhodopsin RxR is deemed to be a base for the technology to convert light into energy and for the technology to use light to control biological functions, and is promising for application to biomedical engineering research based on proteins.

Article Information

DOI: 10.1038/srep44427

Authors: Kanae Kanehara, Susumu Yoshizawa, Takashi Tsukamoto, Yuki Sudo

Journal: Scientific Report

Title: A phylogenetically distinctive and extremely heat stable light-driven proton pump from the eubacterium Rubrobacter xylanophilus DSM 9941

Year of Publication: 2017

Volume: 44427

Issue: 7

Okayama University Silicon Valley Office (OUSVO)
Contact: Mototaka Senda, Ph.D.
Phone: (1)510-468-3372
rhodopsin RxR, membrane protein

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