Structure of T4moC, the Rieske-type ferredoxin component of toluene 4-monooxygenase.

The structure of the Rieske-type ferredoxin (T4moC) from toluene 4-monooxygenase was determined by X-ray crystallography in the [2Fe-2S](2+) state at a resolution of 1.48 A using single-wavelength anomalous dispersion phasing with the [2Fe-2S] center. The structure consists of ten beta-strands arranged into the three antiparallel beta-sheet topology observed in all Rieske proteins. Trp69 of T4moC is adjacent to the [2Fe-2S] centre, which displaces a loop containing the conserved Pro81 by approximately 8 A away from the [2Fe-2S] cluster compared with the Pro loop in the closest structural and functional homolog, the Rieske-type ferredoxin BphF from biphenyl dioxygenase. In addition, T4moC contains five hydrogen bonds to the [2Fe-2S] cluster compared with three hydrogen bonds in BphF. Moreover, the electrostatic surface of T4moC is distinct from that of BphF. These structural differences are identified as possible contributors to the evolutionary specialization of soluble Rieske-type ferredoxins between the diiron monooxygenases and cis-dihydrodiol-forming dioxygenases.

[1]  D. Flint,et al.  The inactivation of Fe-S cluster containing hydro-lyases by superoxide. , 1993, The Journal of biological chemistry.

[2]  Michael J. Holst,et al.  Numerical solution of the nonlinear Poisson–Boltzmann equation: Developing more robust and efficient methods , 1995, J. Comput. Chem..

[3]  T. Omori,et al.  New Classification System for Oxygenase Components Involved in Ring-Hydroxylating Oxygenations , 2001, Bioscience, biotechnology, and biochemistry.

[4]  B. Fox,et al.  Optimized expression and purification of toluene 4-monooxygenase hydroxylase. , 2000, Protein expression and purification.

[5]  A. Crofts,et al.  Structure and function of cytochrome bc complexes. , 2000, Annual review of biochemistry.

[6]  H. Dobbek,et al.  2-Oxoquinoline 8-monooxygenase oxygenase component: active site modulation by Rieske-[2Fe-2S] center oxidation/reduction. , 2005, Structure.

[7]  R. B. Winter,et al.  Cloning and characterization of a Pseudomonas mendocina KR1 gene cluster encoding toluene-4-monooxygenase , 1991, Journal of bacteriology.

[8]  A. Crofts,et al.  Reduction potentials of Rieske clusters: importance of the coupling between oxidation state and histidine protonation state. , 2003, Biochemistry.

[9]  Z. Otwinowski,et al.  [20] Processing of X-ray diffraction data collected in oscillation mode. , 1997, Methods in enzymology.

[10]  Thomas C Terwilliger,et al.  SOLVE and RESOLVE: automated structure solution and density modification. , 2003, Methods in enzymology.

[11]  B. Fox,et al.  Detection and classification of hyperfine-shifted 1H, 2H, and 15N resonances of the Rieske ferredoxin component of toluene 4-monooxygenase. , 1999, Biochemistry.

[12]  Z. Fujimoto,et al.  Crystal structure of the ferredoxin component of carbazole 1,9a‐dioxygenase of Pseudomonas resinovorans strain CA10, a novel Rieske non‐heme iron oxygenase system , 2005, Proteins.

[13]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[14]  D E McRee,et al.  XtalView/Xfit--A versatile program for manipulating atomic coordinates and electron density. , 1999, Journal of structural biology.

[15]  J. Thompson,et al.  Using CLUSTAL for multiple sequence alignments. , 1996, Methods in enzymology.

[16]  B. Fox,et al.  Recombinant toluene-4-monooxygenase: catalytic and Mössbauer studies of the purified diiron and rieske components of a four-protein complex. , 1996, Biochemistry.

[17]  Christophe G. Lambert,et al.  ESyPred3D: Prediction of proteins 3D structures , 2002, Bioinform..

[18]  B. Fox,et al.  Solution structure of the toluene 4-monooxygenase effector protein (T4moD). , 2001, Biochemistry.

[19]  S. Lippard,et al.  Sequencing and analysis of the Methylococcus capsulatus (Bath) soluble methane monooxygenase genes , 2000 .

[20]  A. Heine,et al.  High-resolution structure of the soluble, respiratory-type Rieske protein from Thermus thermophilus: analysis and comparison. , 2003, Biochemistry.

[21]  R. Ladenstein,et al.  The structure of the soluble domain of an archaeal Rieske iron-sulfur protein at 1.1 A resolution. , 2002, Journal of molecular biology.

[22]  J. G. Leahy,et al.  Evolution of the soluble diiron monooxygenases. , 2003, FEMS microbiology reviews.

[23]  B. Fox,et al.  Combined participation of hydroxylase active site residues and effector protein binding in a para to ortho modulation of toluene 4-monooxygenase regiospecificity. , 2002, Biochemistry.

[24]  Thomas L. Madden,et al.  Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. , 1997, Nucleic acids research.