The first non-turnover voltammetric response from a molybdenum enzyme:: direct electrochemistry of dimethylsulfoxide reductase from Rhodobacter capsulatus

被引:30
作者
Aguey-Zinsou, KF
Bernhardt, PV [1 ]
McEwan, AG
Ridge, JP
机构
[1] Univ Queensland, Dept Chem, Brisbane, Qld 4072, Australia
[2] Univ Queensland, Dept Microbiol & Parasitol, Brisbane, Qld 4072, Australia
来源
JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY | 2002年 / 7卷 / 7-8期
基金
澳大利亚研究理事会;
关键词
voltammetry; molybdenum enzyme; Rhodobacter capsulatus; dimethylsulfoxide reductase;
D O I
10.1007/s00775-002-0374-y
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The first direct voltammetric response from a molybdenum enzyme under non-turnover conditions is reported. Cyclic voltammetry of dimethylsulfoxide reductase from Rhodobacter capsulatus reveals a reversible Mo-VI/V response at + 161 mV followed by a reversible Mo-V/IV response at -102 mV versus NHE at pH 8. The higher potential couple exhibits a pH dependence consistent with protonation upon reduction to the Mo-V state and we have determined the pK(a) for this semi-reduced species to be 9.0. The lower potential couple is pH independent within the range 5 < pH < 10. The optical spectrum of the Mo chromophore has been investigated with spectroelectrochemistry. At high potential, in its resting state, the enzyme exhibits a spectrum characteristic of the Mo-VI form. This changes significantly following bulk electrolysis (-400 mV versus NHE) at an optically transparent, indium-doped tin oxide working electrode, where a single visible electronic maximum at 632 nm is observed, which is comparable with spectra reported previously for the dithionite-reduced enzyme. This two-electron process is chemically reversible by reoxidizing the enzyme at the electrode in the absence of mediators or promoters. The activity of the enzyme has been established by observation of a catalytic current in the presence of DMSO at pH 8, where a sigmoidal (steady state) voltammogram is seen. Electronic supplementary material to this paper (Fig. S 1) can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00775-002-0374-y.
引用
收藏
页码:879 / 883
页数:5
相关论文
共 32 条
  • [21] The 1.3 Å crystal structure of Rhodobacter sphaeroides dimethyl sulfoxide reductase reveals two distinct molybdenum coordination environments
    Li, HK
    Temple, C
    Rajagopalan, KV
    Schindelin, H
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2000, 122 (32) : 7673 - 7680
  • [22] Molybdenum cofactor properties and [Fe-S] cluster coordination in Escherichia coli nitrate reductase A:: Investigation by site-directed mutagenesis of the conserved His-50 residue in the NarG subunit
    Magalon, A
    Asso, M
    Guigliarelli, B
    Rothery, RA
    Bertrand, P
    Giordano, G
    Blasco, F
    [J]. BIOCHEMISTRY, 1998, 37 (20) : 7363 - 7370
  • [23] Molybdenum active centre of DMSO reductase from Rhodobacter capsulatus:: crystal structure of the oxidised enzyme at 1.82-Å resolution and the dithionite-reduced enzyme at 2.8-Å resolution
    McAlpine, AS
    McEwan, AG
    Shaw, AL
    Bailey, S
    [J]. JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY, 1997, 2 (06): : 690 - 701
  • [24] The high resolution crystal structure of DMSO reductase in complex with DMSO
    McAlpine, AS
    McEwan, AG
    Bailey, S
    [J]. JOURNAL OF MOLECULAR BIOLOGY, 1998, 275 (04) : 613 - 623
  • [25] Interactions between the molybdenum cofactor and iron-sulfur clusters of Escherichia coli dimethylsulfoxide reductase
    Rothery, RA
    Trieber, CA
    Weiner, JH
    [J]. JOURNAL OF BIOLOGICAL CHEMISTRY, 1999, 274 (19) : 13002 - 13009
  • [26] Enzyme bioelectrochemistry in cast biomembrane-like films
    Rusling, JF
    [J]. ACCOUNTS OF CHEMICAL RESEARCH, 1998, 31 (06) : 363 - 369
  • [27] Crystal structure of DMSO reductase: Redox-linked changes in molybdopterin coordination
    Schindelin, H
    Kisker, C
    Hilton, J
    Rajagopalan, KV
    Rees, DC
    [J]. SCIENCE, 1996, 272 (5268) : 1615 - 1621
  • [28] Crystal structure of dimethyl sulfoxide reductase from Rhodobacter capsulatus at 1.88 angstrom resolution
    Schneider, F
    Lowe, J
    Huber, R
    Schindelin, H
    Kisker, C
    Knablein, J
    [J]. JOURNAL OF MOLECULAR BIOLOGY, 1996, 263 (01) : 53 - 69
  • [29] Structure of the molybdenum site of Rhodobacter sphaeroides biotin sulfoxide reductase
    Temple, CA
    George, GN
    Hilton, JC
    George, MJ
    Prince, RC
    Barber, MJ
    Rajagopalan, KV
    [J]. BIOCHEMISTRY, 2000, 39 (14) : 4046 - 4052
  • [30] Consequences of removal of a molybdenum ligand (DmsA-Ser-176) of Escherichia coli dimethyl sulfoxide reductase
    Trieber, CA
    Rothery, RA
    Weiner, JH
    [J]. JOURNAL OF BIOLOGICAL CHEMISTRY, 1996, 271 (44) : 27339 - 27345