Research Topics
| ANTONY CROFTSSummaryAffiliation: University of Illinois Country: USA Publications
Research Grants
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Detail Information
Publications
Proton-coupled electron transfer at the Q(o) site: what type of mechanism can account for the high activation barrier?A R Crofts
Department of Biochemistry, University of Illinois, Urbana 61801, USA
Biochim Biophys Acta 1459:456-66. 2000....- The Q-cycle reviewed: How well does a monomeric mechanism of the bc(1) complex account for the function of a dimeric complex?Antony R Crofts
Department of Biochemistry, University of Illinois at Urbana Champaign, IL 61801, USA
Biochim Biophys Acta 1777:1001-19. 2008..The data can also be interpreted as showing similar coulombic interaction across the dimer interface, and we discuss mechanistic implications... - Marcus treatment of endergonic reactions: a commentaryAntony R Crofts
Department of Biochemistry, University of Illinois at Urbana Champaign, 600 S Mathews Avenue, Urbana, IL 61801, USA
Biochim Biophys Acta 1767:1228-32. 2007..We show that the difference resulted from an algebraic error in development of the endergonic equation... - Proton pumping in the bc1 complex: a new gating mechanism that prevents short circuitsAntony R Crofts
Department of Biochemistry, University of Illinois at Urbana Champaign, Urbana, IL 61801, USA
Biochim Biophys Acta 1757:1019-34. 2006..The mechanism is quite natural, and is well supported by experiments in which the role of a key residue, Glu-295, which facilitates proton transfer from the site through a rotational displacement, has been tested by mutation... - Proton-coupled electron transfer at the Qo-site of the bc1 complex controls the rate of ubihydroquinone oxidationAntony R Crofts
Department of Biochemistry and Center for Biophysics and Computational Biology, University of Illinois at Urbana Champaign, 419 Roger Adams Lab, 600 S Mathews Avenue, Urbana, IL 61801, USA
Biochim Biophys Acta 1655:77-92. 2004.... - The cytochrome bc1 complex: function in the context of structureAntony R Crofts
Department of Biochemistry, and Center for Biophysics and Computational Biology, University of Illinois at Urbana Champaign, Urbana, Illinois 61801, USA
Annu Rev Physiol 66:689-733. 2004..This paper reviews recent advances in our understanding of the mechanism of the bc1 complex and their relation to these physiologically important issues in the context of the structural information available... - The modified Q-cycle explains the apparent mismatch between the kinetics of reduction of cytochromes c1 and bH in the bc1 complexAntony R Crofts
Department of Biochemistry, University of Illinois at Urbana Champaign, Urbana, Illinois 61801, USA
J Biol Chem 278:36191-201. 2003.... - Interactions of quinone with the iron-sulfur protein of the bc(1) complex: is the mechanism spring-loaded?Antony R Crofts
Department of Biochemistry, University of Illinois, Urbana 61801, USA
Biochim Biophys Acta 1555:48-53. 2002..We also discuss recent results from studies of the bypass reactions at the site, which lead to superoxide (SO) production under aerobic conditions, and provide additional information about intermediate states... - Modulation of the midpoint potential of the [2Fe-2S] Rieske iron sulfur center by Qo occupants in the bc1 complexVladimir P Shinkarev
Department of Biochemistry, University of Illinois at Urbana-Champaign, 156 Davenport Hall, 607 South Mathews Avenue, Urbana, Illinois 6l80l
Biochemistry 41:14372-82. 2002.... - Atomic resolution structures of rieske iron-sulfur protein: role of hydrogen bonds in tuning the redox potential of iron-sulfur clustersDerrick J Kolling
Center for Biophysics and Computational Biology, University of Illinois at Urbana Champaign, 600 S Mathews Avenue, Urbana, IL 61801, USA
Structure 15:29-38. 2007..These studies provide a detailed structure-function dissection of the role of hydrogen bonds in tuning the redox potentials of [2Fe-2S] clusters... - Modifications of protein environment of the [2Fe-2S] cluster of the bc1 complex: effects on the biophysical properties of the rieske iron-sulfur protein and on the kinetics of the complexSangmoon Lhee
Center for Biophysics and Computational Biology, University of Illinois, Urbana, Illinois 61801, USA
J Biol Chem 285:9233-48. 2010..The proton-first-then-electron model proposed accounts naturally for the effects of mutation on the overall reaction... - Proton environment of reduced Rieske iron-sulfur cluster probed by two-dimensional ESEEM spectroscopyDerrick R J Kolling
Center for Biophysics and Computational Biology, University of Illinois, Urbana, Illinois 61801, USA
J Phys Chem A 113:653-67. 2009..The approach demonstrated here provides a paradigm for a wide range of studies in which hydrogen-bonding interactions with metallic centers has a crucial role in understanding the function... - D1-arginine257 mutants (R257E, K, and Q) of Chlamydomonas reinhardtii have a lowered QB redox potential: analysis of thermoluminescence and fluorescence measurementsStuart Rose
Department of Biochemistry, University of Illinois at Urbana Champaign, Urbana, IL 61801, USA
Photosynth Res 98:449-68. 2008..We discuss an indirect mechanism mediated through electrostatic and/or surface charge effects and the possibility of more pleiotropic effects arising from decreased stability of the D1/D2 and D1/CP47 interfaces... - Hydrogen bonds between nitrogen donors and the semiquinone in the Qi-site of the bc1 complexSergei A Dikanov
Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois 61801, USA
J Biol Chem 282:25831-41. 2007..A mechanistic role for this residue is supported by kinetic experiments with mutant strains N221T, N221H, N221I, N221S, N221P, and N221D, all of which showed some inhibition but retained partial turnover... - Identification of hydrogen bonds to the Rieske cluster through the weakly coupled nitrogens detected by electron spin echo envelope modulation spectroscopySergei A Dikanov
Department of Veterinary Clinical Medicine, University of Illinois, Urbana, Illinois 61801, USA
J Biol Chem 281:27416-25. 2006.... - In situ kinetics of cytochromes c1 and c2Vladimir P Shinkarev
Department of Biochemistry, University of Illinois, 156 Davenport Hall, 607 South Mathews Avenue, Urbana, Illinois 6l80l, USA
Biochemistry 45:7897-903. 2006..The successful spectral deconvolution of cyt c(1) and c(2), and inclusion of both cytochromes in the kinetic analysis, significantly increase the data available for mechanistic understanding of bc(1) turnover in situ... - Spectral and kinetic resolution of the bc1 complex components in situ: a simple and robust alternative to the traditional difference wavelength approachVladimir P Shinkarev
Department of Biochemistry, University of Illinois at Urbana Champaign, 156 Davenport Hall, 607 South Mathews Avenue, Urbana, 6l80l, USA
Biochim Biophys Acta 1757:273-83. 2006..This is the first study in which the kinetics of all cytochrome and reaction center components of the bc(1) complex functioning in situ have been measured simultaneously, with full deconvolution over an extended time range... - Spectral analysis of the bc(1) complex components in situ: beyond the traditional difference approachVladimir P Shinkarev
Department of Biochemistry, University of Illinois at Urbana Champaign, 156 Davenport Hall, 607 South Mathews Avenue, Urbana, IL 61801, USA
Biochim Biophys Acta 1757:67-77. 2006..of individual components is necessary. We conclude that further exploration of mechanisms of the bc(1) complex, will require LS deconvolution for reliable measurement of the kinetics of individual components of the complex in situ... - Hydrogen bonds involved in binding the Qi-site semiquinone in the bc1 complex, identified through deuterium exchange using pulsed EPRSergei A Dikanov
Department of Biochemistry, University of Illinois at Urbana--Champaign, Urbana, Illinois 61801, USA
J Biol Chem 279:15814-23. 2004..They provide pathways for exchange of protons within the site and with the exteriors, needed to accommodate the different hydrogen bonding requirements of different quinone species during catalysis... - The reduced [2Fe-2S] clusters in adrenodoxin and Arthrospira platensis ferredoxin share spin density with protein nitrogens, probed using 2D ESEEMSergei A Dikanov
Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL 61801, USA
Phys Chem Chem Phys 11:6807-19. 2009..A possible influence of redox-linked structural changes on ESEEM data is analyzed using available structures for related proteins in two redox states... - Reduction potentials of Rieske clusters: importance of the coupling between oxidation state and histidine protonation stateYanbing Zu
Medical Research Council Dunn Human Nutrition Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge, CB2 2XY, United Kingdom
Biochemistry 42:12400-8. 2003..Implications for the mechanism of quinol oxidation at the Q(O) site of the cytochrome bc(1) and b(6)f complexes are discussed... - The interaction of the Rieske iron-sulfur protein with occupants of the Qo-site of the bc1 complex, probed by electron spin echo envelope modulationRimma I Samoilova
Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russia
J Biol Chem 277:4605-8. 2002.... - Multiple Q-cycle bypass reactions at the Qo site of the cytochrome bc1 complexFlorian Muller
Institute of Biological Chemistry, 289 Clark Hall, Washington State University, Pullman, WA 99164-6340, USA
Biochemistry 41:7866-74. 2002..Given that myxothiazol blocks cyt b reduction whereas antimycin A promotes it, we propose that this second bypass occurs by reduction of the Q(o) site semiquinone by prereduced cyt b(L)... - Characterization of the pH-dependent resonance Raman transitions of archaeal and bacterial Rieske [2Fe-2S] proteinsToshio Iwasaki
Department of Biochemistry and Molecular Biology, Nippon Medical School, Sendagi, Bunkyo ku, Tokyo 113 8602, Japan
J Am Chem Soc 126:4788-9. 2004.... - Resonance Raman characterization of archaeal and bacterial Rieske protein variants with modified hydrogen bond network around the [2Fe-2S] centerToshio Iwasaki
Department of Biochemistry and Molecular Biology, Nippon Medical School, Sendagi, Tokyo, Japan
Protein Sci 15:2019-24. 2006..This is not observed in the case of the hydrogen bond between the bridging sulfide ligand (S(b)) and Ser-Ogamma, which is weak and/or unfavorably oriented for extensive coupling with the Fe-S(b/t) stretching vibrations... - Exploration of ligands to the Qi site semiquinone in the bc1 complex using high-resolution EPRDerrick R J Kolling
Departments of Biochemistry and Veterinary Clinical Medicine
J Biol Chem 278:39747-54. 2003..5-3.1 A for the O-N distance between the carbonyl of SQ and the nitrogen was estimated. The mechanistic significance is discussed in the context of a dynamic role for the movement of His-217 in proton transfer to the site...
Research Grants
- MOLECULAR ARCHITECTURE OF UQH2: CYTC2 OXIDOREDUCTASEANTONY CROFTS; Fiscal Year: 2003..Natural inhibitors block turnover by mimicking quinone at the catalytic sites, and commercial interest has centered on the possibility of using these as green pesticides. ..
- Molecular Architecture of UGH2-cytc2 oxidoreductaseANTONY CROFTS; Fiscal Year: 2007..Key features of the mechanism are the driving forces for the rate limiting step, and the conformational dynamics that protect the semiquinone from reaction with oxygen. ..
- MOLECULAR ARCHITECTURE OF UQH2: CYT C2 OXIDOREDUCTASEANTONY CROFTS; Fiscal Year: 1993..The software developed allows us to select strains with specific phenotypic attributes using false color coding of images, and measurement of induction kinetics of individual colonies...
- MOLECULAR ARCHITECTURE OF UQH2:CYT C2 OXIDOREDUCTASEAntony R Crofts; Fiscal Year: 2010..The complex is also a target for anti- malarial drugs, and for fungicides and pesticides, important both in medicine and agriculture. ..