1
|
Tahara S, Takeuchi S, Abe-Yoshizumi R, Inoue K, Ohtani H, Kandori H, Tahara T. Origin of the Reactive and Nonreactive Excited States in the Primary Reaction of Rhodopsins: pH Dependence of Femtosecond Absorption of Light-Driven Sodium Ion Pump Rhodopsin KR2. J Phys Chem B 2018; 122:4784-4792. [DOI: 10.1021/acs.jpcb.8b01934] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | | | | | - Keiichi Inoue
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Hiroyuki Ohtani
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan
| | | | | |
Collapse
|
2
|
Kandori H, Inoue K, Tsunoda SP. Light-Driven Sodium-Pumping Rhodopsin: A New Concept of Active Transport. Chem Rev 2018. [DOI: 10.1021/acs.chemrev.7b00548] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
| | - Keiichi Inoue
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Satoshi P. Tsunoda
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|
3
|
Chen HF, Inoue K, Ono H, Abe-Yoshizumi R, Wada A, Kandori H. Time-resolved FTIR study of light-driven sodium pump rhodopsins. Phys Chem Chem Phys 2018; 20:17694-17704. [DOI: 10.1039/c8cp02599a] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Light-driven sodium ion pump rhodopsin (NaR) is a new functional class of microbial rhodopsin. Present step-scan time-resolved FTIR spectroscopy revealed that the K, L and O intermediates of NaRs contain 13-cis retinal with similar distortion.
Collapse
Affiliation(s)
- Hui-Fen Chen
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Taiwan
- Department of Life Science and Applied Chemistry
| | - Keiichi Inoue
- Department of Life Science and Applied Chemistry
- Nagoya Institute of Technology
- Nagoya 466-8555
- Japan
- OptoBioTechnology Research Center
| | - Hikaru Ono
- Department of Life Science and Applied Chemistry
- Nagoya Institute of Technology
- Nagoya 466-8555
- Japan
| | - Rei Abe-Yoshizumi
- Department of Life Science and Applied Chemistry
- Nagoya Institute of Technology
- Nagoya 466-8555
- Japan
| | - Akimori Wada
- Laboratory of Organic Chemistry for Life Science
- Kobe Pharmaceutical University
- Kobe 658-8558
- Japan
| | - Hideki Kandori
- Department of Life Science and Applied Chemistry
- Nagoya Institute of Technology
- Nagoya 466-8555
- Japan
- OptoBioTechnology Research Center
| |
Collapse
|
4
|
From Gene to Function: Cell-Free Electrophysiological and Optical Analysis of Ion Pumps in Nanodiscs. Biophys J 2017; 113:1331-1341. [PMID: 28450130 DOI: 10.1016/j.bpj.2017.03.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/14/2017] [Accepted: 03/27/2017] [Indexed: 12/15/2022] Open
Abstract
Nanodiscs that hold a lipid bilayer surrounded by a boundary of scaffold proteins have emerged as a powerful tool for membrane protein solubilization and analysis. By combining nanodiscs and cell-free expression technologies, even completely detergent-free membrane protein characterization protocols can be designed. Nanodiscs are compatible with various techniques, and due to their bilayer environment and increased stability, they are often superior to detergent micelles or liposomes for membrane protein solubilization. However, transport assays in nanodiscs have not been conducted so far, due to limitations of the two-dimensional nature of nanodisc membranes that offers no compartmentalization. Here, we study Krokinobacter eikastus rhodopsin-2 (KR2), a microbial light-driven sodium or proton pump, with noncovalent mass-spectrometric, electrophysiological, and flash photolysis measurements after its cotranslational insertion into nanodiscs. We demonstrate the feasibility of adsorbing nanodiscs containing KR2 to an artificial bilayer. This allows us to record light-induced capacitive currents that reflect KR2's ion transport activity. The solid-supported membrane assay with nanodisc samples provides reliable control over the ionic condition and information of the relative ion activity of this promiscuous pump. Our strategy is complemented with flash photolysis data, where the lifetimes of different photointermediates were determined at different ionic conditions. The advantage of using identical samples to three complementary approaches allows for a comprehensive comparability. The cell-free synthesis in combination with nanodiscs provides a defined hydrophobic lipid environment minimizing the detergent dependence often seen in assays with membrane proteins. KR2 is a promising tool for optogenetics, thus directed engineering to modify ion selectivity can be highly beneficial. Our approach, using the fast generation of functional ion pumps incorporated into nanodiscs and their subsequent analysis by several biophysical techniques, can serve as a versatile screening and engineering platform. This may open new avenues for the study of ion pumps and similar electrogenic targets.
Collapse
|
5
|
Inoue K. The Study and Application of Photoreceptive Membrane Protein, Rhodopsin. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2016. [DOI: 10.1246/bcsj.20160235] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
6
|
Konno M, Kato Y, Kato HE, Inoue K, Nureki O, Kandori H. Mutant of a Light-Driven Sodium Ion Pump Can Transport Cesium Ions. J Phys Chem Lett 2016; 7:51-55. [PMID: 26740141 DOI: 10.1021/acs.jpclett.5b02385] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Krokinobacter eikastus rhodopsin 2 (KR2) is a light-driven Na(+) pump found in marine bacterium. KR2 pumps Li(+) and Na(+), but it becomes an H(+) pump in the presence of K(+), Rb(+), and Cs(+). Site-directed mutagenesis of the cytoplasmic surface successfully converted KR2 into a light-driven K(+) pump, suggesting that ion selectivity is determined at the cytoplasmic surface. Here we extended this research and successfully created a light-driven Cs(+) pump. KR2 N61L/G263F pumps Cs(+) as well as other monovalent cations in the presence of a protonophore. Ion-transport activities correlated with the additive volume of the residues at 61 and 263. The result suggests that an ion-selectivity filter is affected by these two residues and functions by strict exclusion of K(+) and larger cations in the wild type (N61/G263). In contrast, introduction of large residues possibly destroys local structures of the ion-selectivity filter, leading to the permeation of K(+) (P61/W263) and Cs(+) (L61/F263).
Collapse
Affiliation(s)
- Masae Konno
- Department of Frontier Materials, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| | - Yoshitaka Kato
- Department of Frontier Materials, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| | - Hideaki E Kato
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo , 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Keiichi Inoue
- Department of Frontier Materials, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
- PRESTO, Japan Science and Technology Agency (JST) , 4-1-8 Honcho Kawaguchi, Saitama, 332-0012, Japan
| | - Osamu Nureki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo , 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Hideki Kandori
- Department of Frontier Materials, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| |
Collapse
|
7
|
Kato Y, Inoue K, Kandori H. Kinetic Analysis of H(+)-Na(+) Selectivity in a Light-Driven Na(+)-Pumping Rhodopsin. J Phys Chem Lett 2015; 6:5111-5115. [PMID: 26673197 DOI: 10.1021/acs.jpclett.5b02371] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Krokinobacter eikastus rhodopsin 2 (KR2) is a recently identified light-driven Na(+) pump from a marine bacterium. KR2 pumps Na(+) in NaCl solution but pumps H(+) in the absence of Na(+) and Li(+). The Na(+) transport mechanism in KR2 has been extensively studied, whereas understanding of the H(+) transport mechanism is very limited. Here we studied ion uptake mechanisms and H(+)-Na(+) selectivity using flash photolysis. The results show that decay of the blue-shifted M intermediate is dependent on both [Na(+)] and [H(+)], indicating that KR2 competitively uptakes Na(+) or H(+) upon M decay. Comprehensive concentration dependence of Na(+) and H(+) revealed that the rate constant of H(+) uptake (kH) was much larger than that of Na(+) uptake (kNa) with a ratio (kH/kNa) of >10(3). Therefore, KR2 pumps only H(+) when Na(+) and H(+) concentrations are similar. On the contrary, KR2 pumps Na(+) exclusively under physiological conditions in which [Na(+)] is much greater than [H(+)].
Collapse
Affiliation(s)
- Yoshitaka Kato
- Department of Frontier Materials, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| | - Keiichi Inoue
- Department of Frontier Materials, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
- PRESTO, Japan Science and Technology Agency (JST) , 4-1-8 Honcho Kawaguchi, Saitama, 332-0012, Japan
| | - Hideki Kandori
- Department of Frontier Materials, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology Research Center, Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555, Japan
| |
Collapse
|