skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The surface metal site in Blc. viridis photosynthetic bacterial reaction centers: Cu{sup 2+} as a probe of structure, location, and flexibility.

Abstract

Metal ion binding to a surface site on photosynthetic reaction centers (RCs) modulates light-induced electron and proton transfer events in the RC. Whereas many studies have elucidated aspects of metal ion modulation events in Rhodobacter sphaeroides RCs, much less is understood about the surface site in Blastochloris viridis (Blc. viridis) RCs. Interestingly, electron paramagnetic resonance studies revealed two spectroscopically distinct Cu{sup 2+} surface site environments in Blc. viridis RCs. Herein, Cu{sup 2+} has been used to spectroscopically probe the structure of these Cu{sup 2+} site(s) in response to freezing conditions, temperature, and charge separation. One Cu{sup 2+} environment in Blc. viridis RCs, termed CuA, exhibits temperature-dependent conformational flexibility. Different conformation states of the CuA{sup 2+} site are trapped when the RC is frozen in the dark either by fast-freeze or slow-freeze procedure. The second Cu{sup 2+} environment, termed CuB, is structurally invariant to different freezing conditions and shows resolved hyperfine coupling to three nitrogen atoms. Cu{sup 2+} is most likely binding at the same location on the RC, but in different coordination environments which may reflect two distinct conformational states of the isolated Blc. viridis RC protein.

Authors:
; ; ;  [1]
  1. (Chemical Sciences and Engineering Division)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1010892
Report Number(s):
ANL/CSE/JA-63959
Journal ID: ISSN 0937-9347; APMREI; TRN: US1102092
DOE Contract Number:  
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Appl. Magn. Reson.; Journal Volume: 38; Journal Issue: 1 ; 2010
Country of Publication:
United States
Language:
ENGLISH
Subject:
59 BASIC BIOLOGICAL SCIENCES; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ATOMS; ELECTRON SPIN RESONANCE; ELECTRONS; FLEXIBILITY; FREEZING; MODULATION; NITROGEN; PHOTOSYNTHETIC REACTION CENTERS; PROBES; PROTONS

Citation Formats

Utschig, L. M., Dalosto, S. D., Thurnauer, M. C., and Poluektov, O. G.. The surface metal site in Blc. viridis photosynthetic bacterial reaction centers: Cu{sup 2+} as a probe of structure, location, and flexibility.. United States: N. p., 2010. Web. doi:10.1007/s00723-009-0116-1.
Utschig, L. M., Dalosto, S. D., Thurnauer, M. C., & Poluektov, O. G.. The surface metal site in Blc. viridis photosynthetic bacterial reaction centers: Cu{sup 2+} as a probe of structure, location, and flexibility.. United States. doi:10.1007/s00723-009-0116-1.
Utschig, L. M., Dalosto, S. D., Thurnauer, M. C., and Poluektov, O. G.. Fri . "The surface metal site in Blc. viridis photosynthetic bacterial reaction centers: Cu{sup 2+} as a probe of structure, location, and flexibility.". United States. doi:10.1007/s00723-009-0116-1.
@article{osti_1010892,
title = {The surface metal site in Blc. viridis photosynthetic bacterial reaction centers: Cu{sup 2+} as a probe of structure, location, and flexibility.},
author = {Utschig, L. M. and Dalosto, S. D. and Thurnauer, M. C. and Poluektov, O. G.},
abstractNote = {Metal ion binding to a surface site on photosynthetic reaction centers (RCs) modulates light-induced electron and proton transfer events in the RC. Whereas many studies have elucidated aspects of metal ion modulation events in Rhodobacter sphaeroides RCs, much less is understood about the surface site in Blastochloris viridis (Blc. viridis) RCs. Interestingly, electron paramagnetic resonance studies revealed two spectroscopically distinct Cu{sup 2+} surface site environments in Blc. viridis RCs. Herein, Cu{sup 2+} has been used to spectroscopically probe the structure of these Cu{sup 2+} site(s) in response to freezing conditions, temperature, and charge separation. One Cu{sup 2+} environment in Blc. viridis RCs, termed CuA, exhibits temperature-dependent conformational flexibility. Different conformation states of the CuA{sup 2+} site are trapped when the RC is frozen in the dark either by fast-freeze or slow-freeze procedure. The second Cu{sup 2+} environment, termed CuB, is structurally invariant to different freezing conditions and shows resolved hyperfine coupling to three nitrogen atoms. Cu{sup 2+} is most likely binding at the same location on the RC, but in different coordination environments which may reflect two distinct conformational states of the isolated Blc. viridis RC protein.},
doi = {10.1007/s00723-009-0116-1},
journal = {Appl. Magn. Reson.},
number = 1 ; 2010,
volume = 38,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 2010},
month = {Fri Jan 01 00:00:00 EST 2010}
}