PMID- 36708913
OWN - NLM
STAT- MEDLINE
DCOM- 20230310
LR  - 20230316
IS  - 1879-2650 (Electronic)
IS  - 0005-2728 (Linking)
VI  - 1864
IP  - 2
DP  - 2023 Apr 1
TI  - Calcium-bound structure of bovine cytochrome c oxidase.
PG  - 148956
LID - S0005-2728(23)00002-6 [pii]
LID - 10.1016/j.bbabio.2023.148956 [doi]
AB  - The crystal structure of bovine cytochrome c oxidase (CcO) shows a sodium ion 
      (Na(+)) bound to the surface of subunit I. Changes in the absorption spectrum of 
      heme a caused by calcium ions (Ca(2+)) are detected as small red shifts, and 
      inhibition of enzymatic activity under low turnover conditions is observed by 
      addition of Ca(2+) in a competitive manner with Na(+). In this study, we 
      determined the crystal structure of Ca(2+)-bound bovine CcO in the oxidized and 
      reduced states at 1.7 A resolution. Although Ca(2+) and Na(+) bound to the same 
      site of oxidized and reduced CcO, they led to different coordination geometries. 
      Replacement of Na(+) with Ca(2+) caused a small structural change in the loop 
      segments near the heme a propionate and formyl groups, resulting in spectral 
      changes in heme a. Redox-coupled structural changes observed in the Ca(2+)-bound 
      form were the same as those previously observed in the Na(+)-bound form, 
      suggesting that binding of Ca(2+) does not severely affect enzymatic function, 
      which depends on these structural changes. The relation between the Ca(2+) 
      binding and the inhibitory effect during slow turnover, as well as the possible 
      role of bound Ca(2+) are discussed.
CI  - Copyright (c) 2023 The Authors. Published by Elsevier B.V. All rights reserved.
FAU - Muramoto, Kazumasa
AU  - Muramoto K
AD  - Graduate School of Science, University of Hyogo, 3-2-1 Kouto, Kamigori, Ako, 
      Hyogo 678-1297, Japan. Electronic address: muramoto@sci.u-hyogo.ac.jp.
FAU - Shinzawa-Itoh, Kyoko
AU  - Shinzawa-Itoh K
AD  - Graduate School of Science, University of Hyogo, 3-2-1 Kouto, Kamigori, Ako, 
      Hyogo 678-1297, Japan. Electronic address: shinzawa@sci.u-hyogo.ac.jp.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20230125
PL  - Netherlands
TA  - Biochim Biophys Acta Bioenerg
JT  - Biochimica et biophysica acta. Bioenergetics
JID - 101731706
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
RN  - SY7Q814VUP (Calcium)
RN  - 0 (Ions)
RN  - 9NEZ333N27 (Sodium)
SB  - IM
MH  - Cattle
MH  - Animals
MH  - *Electron Transport Complex IV/metabolism
MH  - *Calcium/metabolism
MH  - Oxidation-Reduction
MH  - Ions/metabolism
MH  - Sodium/metabolism
OTO - NOTNLM
OT  - Calcium ion
OT  - Cytochrome c oxidase
OT  - X-ray crystallography
COIS- Declaration of competing interest The authors declare that they have no conflict 
      of interest.
EDAT- 2023/01/29 06:00
MHDA- 2023/03/11 06:00
CRDT- 2023/01/28 19:26
PHST- 2022/10/24 00:00 [received]
PHST- 2023/01/11 00:00 [revised]
PHST- 2023/01/20 00:00 [accepted]
PHST- 2023/01/29 06:00 [pubmed]
PHST- 2023/03/11 06:00 [medline]
PHST- 2023/01/28 19:26 [entrez]
AID - S0005-2728(23)00002-6 [pii]
AID - 10.1016/j.bbabio.2023.148956 [doi]
PST - ppublish
SO  - Biochim Biophys Acta Bioenerg. 2023 Apr 1;1864(2):148956. doi: 
      10.1016/j.bbabio.2023.148956. Epub 2023 Jan 25.