A light-driven proton pump from Haloterrigena turkmenica: Functional expression in Escherichia coli membrane and coupling with a H{sup +} co-transporter
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812 (Japan)
- Laboratory of Biomolecular Systems, Creative Research Initiative 'Sosei' (CRIS), Hokkaido University, Sapporo 001-0021 (Japan)
- Center for Gene Research, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan)
A gene encoding putative retinal protein was cloned from Haloterrigena turkmenica (JCM9743). The deduced amino acid sequence was most closely related to that of deltarhodopsin, which functions as a light-driven H{sup +} pump and was identified in a novel strain Haloterrigena sp. arg-4 (K. Ihara, T. Uemura, I. Katagiri, T. Kitajima-Ihara, Y. Sugiyama, Y. Kimura, Y. Mukohata, Evolution of the archaeal rhodopsins: Evolution rate changes by gene duplication and functional differentiation, J. Mol. Biol. 285 (1999) 163-174. GenBank Accession No. AB009620). Thus, we called the present protein H. turkmenica deltarhodopsin (HtdR) in this report. Differing from the Halobacterium salinarum bacteriorhodopsin (bR), functional expression of HtdR was achieved in Escherichia coli membrane with a high yield of 10-15mg protein/L culture. The photocycle of purified HtdR was similar to that of bR. The photo-induced electrogenic proton pumping activity of HtdR was verified. We co-expressed both HtdR and EmrE, a proton-coupled multi-drug efflux transporter in E. coli, and the cells successfully extruded ethidium, a substrate of EmrE, on illumination.
- OSTI ID:
- 20798826
- Journal Information:
- Biochemical and Biophysical Research Communications, Vol. 341, Issue 2; Other Information: DOI: 10.1016/j.bbrc.2005.12.181; PII: S0006-291X(06)00011-8; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0006-291X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Light-independent phospholipid scramblase activity of bacteriorhodopsin from Halobacterium salinarum
Proton transport by halorhodopsin