TY - JOUR
T1 - A nanosecond time-resolved XFEL analysis of structural changes associated with CO release from cytochrome C oxidase
AU - Shimada, Atsuhiro
AU - Kubo, Minoru
AU - Baba, Seiki
AU - Yamashita, Keitaro
AU - Hirata, Kunio
AU - Ueno, Go
AU - Nomura, Takashi
AU - Kimura, Tetsunari
AU - Shinzawa-Itoh, Kyoko
AU - Baba, Junpei
AU - Hatano, Keita
AU - Eto, Yuki
AU - Miyamoto, Akari
AU - Murakami, Hironori
AU - Kumasaka, Takashi
AU - Owada, Shigeki
AU - Tono, Kensuke
AU - Yabashi, Makina
AU - Yamaguchi, Yoshihiro
AU - Yanagisawa, Sachiko
AU - Sakaguchi, Miyuki
AU - Ogura, Takashi
AU - Komiya, Ryo
AU - Yan, Jiwang
AU - Yamashita, Eiki
AU - Yamamoto, Masaki
AU - Ago, Hideo
AU - Yoshikawa, Shinya
AU - Tsukihara, Tomitake
N1 - Funding Information:
This work was supported by the X-ray Free Electron Laser Priority Strategy Program of the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) (T.O. and H.A.). T. Kimura is supported by the K-CONNEX program. This work was supported by Japan Science and Technology Agency (JST) Core Research for Evolutional Science and Technology (K.H., G.U., and T.T.), JST Precursory Research for Embryonic Science and Technology (M.K. and K.H.), and Pioneering Project "Dynamic Structural Biology" of RIKEN (M.K. and M. Yamamoto) and by Photon and Quantum Basic Research Coordinated Development Program (to T.T., S. Yoshikawa, and K.S.-I.), provided by MEXT. Support is also provided by Japan Society for the Promotion of Science KAKENHI grants 26291033 (to S. Yoshikawa), 15K18493 (to A.S.), and 15H03841 (to M.K.) and Innovative Areas "3D Active-Site Science" 15H01055 (to M.K.) and by Machine Tool Engineering Foundation (R.K. and J.Y.).
Publisher Copyright:
© Copyright 2017 The Authors, some rights reserved.
PY - 2017/7/5
Y1 - 2017/7/5
N2 - Bovine cytochrome c oxidase (CcO), a 420-kDa membrane protein, pumps protons using electrostatic repulsion between protons transferred through a water channel and net positive charges created by oxidation of heme a (Fea) for reduction of O2 at heme a3 (Fea3). For this process to function properly, timing is essential: The channelmust be closed after collection of the protons to be pumped and before Fea oxidation. If the channel were to remain open, spontaneous backflow of the collected protons would occur. For elucidation of the channel closure mechanism, the opening of the channel, which occurs upon release of COfrom CcO, is investigated by newly developed time-resolved x-ray freeelectron laser and infrared techniqueswith nanosecond time resolution. The opening process indicates that CuB senses completion of proton collection and binds O2 before binding to Fea3 to close the water channel using a conformational relay system, which includes CuB, heme a3, and a transmembrane helix, to block backflow of the collected protons.
AB - Bovine cytochrome c oxidase (CcO), a 420-kDa membrane protein, pumps protons using electrostatic repulsion between protons transferred through a water channel and net positive charges created by oxidation of heme a (Fea) for reduction of O2 at heme a3 (Fea3). For this process to function properly, timing is essential: The channelmust be closed after collection of the protons to be pumped and before Fea oxidation. If the channel were to remain open, spontaneous backflow of the collected protons would occur. For elucidation of the channel closure mechanism, the opening of the channel, which occurs upon release of COfrom CcO, is investigated by newly developed time-resolved x-ray freeelectron laser and infrared techniqueswith nanosecond time resolution. The opening process indicates that CuB senses completion of proton collection and binds O2 before binding to Fea3 to close the water channel using a conformational relay system, which includes CuB, heme a3, and a transmembrane helix, to block backflow of the collected protons.
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U2 - 10.1126/sciadv.1603042
DO - 10.1126/sciadv.1603042
M3 - Article
C2 - 28740863
AN - SCOPUS:85034426685
VL - 3
JO - Science advances
JF - Science advances
SN - 2375-2548
IS - 7
M1 - e1603042
ER -