PMID- 29859163
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20200420
IS  - 1879-2650 (Electronic)
IS  - 0005-2728 (Linking)
VI  - 1859
IP  - 10
DP  - 2018 Oct
TI  - Performance of a time-resolved IR facility for assessment of protonation states 
      and polarity changes in carboxyl groups in a large membrane protein, mammalian 
      cytochrome c oxidase, under turnover conditions in a sub-millisecond time 
      resolution.
PG  - 1045-1050
LID - S0005-2728(18)30131-2 [pii]
LID - 10.1016/j.bbabio.2018.05.015 [doi]
AB  - Time-resolved IR analyses for the protonation and polarity changes of carboxyl 
      groups involved in proton pump enzymes under turnover conditions are 
      indispensable for elucidation of their proton-pump mechanisms. We have developed 
      a new time-resolved infrared facility by introducing a flow system for 
      transferring highly concentrated and thus viscous protein solution to a thin 
      (50 mum) flow cell equipped in a highly sensitive IR spectrometer constructed with 
      the femtosecond mid-IR pulse laser with spectral width of 350 cm(-1) as an IR 
      white light source equipped with multi-channel MCT detector. This facility 
      equipped with O(2) supply system enables the sub-millisecond time scale infrared 
      measurements of the O(2) reduction coupled with proton pumping by bovine 
      cytochrome c oxidase (CcO) initiated by CO-flash photolysis in the COOH 
      (1725-1770 cm(-1)) region with the accuracy of about 10 muO.D. under the 
      background O.D. of 1. The facility identifies a band intensity change at 
      ~1744 cm(-1) assignable to protonation of a carboxyl group coupled with a single 
      electron transfer to the O(2) reduction center within 1 ms after initiation of 
      the reaction. The results suggest that the facility detects protonation of a 
      single carboxyl group included in large proteins like as CcO (210 kDa). The 
      present facility sensitively identifies also polarity changes in COOH group by 
      detecting shifts of the bands near 1750 cm(-1) and 1760 cm(-1), without 
      significant intensity changes. These findings show the performance of this 
      facility sufficiently high for providing crucial information for understanding 
      the proton transferring mechanisms of protein carboxyl groups.
CI  - Copyright (c) 2018 Elsevier B.V. All rights reserved.
FAU - Li, Chen
AU  - Li C
AD  - Department of Life Science, Graduate School of Life Science, University of Hyogo, 
      3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, JAPAN.
FAU - Nishiguchi, Tatsuhito
AU  - Nishiguchi T
AD  - Department of Life Science, Graduate School of Life Science, University of Hyogo, 
      3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, JAPAN.
FAU - Shinzawa-Itoh, Kyoko
AU  - Shinzawa-Itoh K
AD  - Picobiology Institute, Graduate School of Life Science, University of Hyogo, 
      3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, JAPAN.
FAU - Yoshikawa, Shinya
AU  - Yoshikawa S
AD  - Picobiology Institute, Graduate School of Life Science, University of Hyogo, 
      3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, JAPAN.
FAU - Ogura, Takashi
AU  - Ogura T
AD  - Department of Life Science, Graduate School of Life Science, University of Hyogo, 
      3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, JAPAN; Picobiology Institute, 
      Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, 
      Hyogo 678-1297, JAPAN.
FAU - Nakashima, Satoru
AU  - Nakashima S
AD  - Picobiology Institute, Graduate School of Life Science, University of Hyogo, 
      3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, JAPAN. Electronic address: 
      n_satoru@sci.u-hyogo.ac.jp.
LA  - eng
PT  - Journal Article
DEP - 20180530
PL  - Netherlands
TA  - Biochim Biophys Acta Bioenerg
JT  - Biochimica et biophysica acta. Bioenergetics
JID - 101731706
SB  - IM
OTO - NOTNLM
OT  - Cytochrome c oxidase
OT  - Proton pumping mechanism
OT  - Protonated carboxyl group
OT  - Time-resolved infrared spectroscopy
EDAT- 2018/06/03 06:00
MHDA- 2018/06/03 06:01
CRDT- 2018/06/03 06:00
PHST- 2017/11/08 00:00 [received]
PHST- 2018/05/23 00:00 [revised]
PHST- 2018/05/24 00:00 [accepted]
PHST- 2018/06/03 06:00 [pubmed]
PHST- 2018/06/03 06:01 [medline]
PHST- 2018/06/03 06:00 [entrez]
AID - S0005-2728(18)30131-2 [pii]
AID - 10.1016/j.bbabio.2018.05.015 [doi]
PST - ppublish
SO  - Biochim Biophys Acta Bioenerg. 2018 Oct;1859(10):1045-1050. doi: 
      10.1016/j.bbabio.2018.05.015. Epub 2018 May 30.