Orientationally-selected two-dimensional ESEEM spectroscopy of the Rieske-type iron-sulfur cluster in 2,4,5-trichlorophenoxyacetate monooxygenase from Burkholderia cepacis AC1100

Journal Article · Wed Sep 04 04:00:00 EDT 1996 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/ja960781x· OSTI ID:380901

Dikanov, S A ^[1]; Xun, L ^[2]; Karpiel, A B; Bowman, M K ^[1]; Tyryshkin, A M ^[3]

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1. Pacific Northwest National Lab., Richland, WA (United States)
2. Washington State Univ., Richland, WA (United States)
3. Inst. of Chemical Kinetics and Combustion, Novosibirsk (Russian Federation)

Burkholderia cepacia AC1100 is able to use the chlorinated compound 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) as the sole source of carbon and energy. This paper describes the application of two-dimensional ESEEM (called HYSCORE) spectroscopy for further characterization of the nitrogens surrounding the reduced Rieske-type cluster. The HYSCORE spectra measured at field positions in the neighborhood of the principal directions of the g tensor contain major contributions from cross-peaks correlating the two double-quantum transitions from each histidine nitrogen. These allow the estimation of the diagonal components of the hyperfine tensors along the principal axes of the g tensor: 4.05, 3.88, and 4.01 MHz (N1) and 4.71, 5.07, and 5.02 MHz (N2). HYSCORE measurements have been also performed with the reduced [2Fe-2S] plant ferredoxin-type cluster with four cysteine ligands in a ferredoxin from Porphira umbilicalis, and spectral features produced by the peptide nitrogen are observed. Similar features also appear in the HYSCORE spectra of the Rieske cluster. Systematic differences are observed between 2,4,5-T monooxygenase and published results from related benzene and phthalate dioxygenases that may reflect structural and functional differences in histidine ligation and the nitrogens of nearby amino acids in Rieske-type [2Fe-2S] clusters. 27 refs., 8 figs., 1 tab.

• DOE Contract Number: AC06-76RL01830; FG06-89ER75522; FG06-92RL12451
• OSTI ID: 380901
• Journal Information: Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 35 Vol. 118; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
55 BIOLOGY AND MEDICINE
BASIC STUDIES
AMINO ACIDS
ELECTRON SPECTRA
ELECTRON SPIN RESONANCE
ENZYMES
HISTIDINE
IRON
LIGANDS
MICROORGANISMS
NITROGEN
ORGANIC CHLORINE COMPOUNDS
OXYGENASES
SOLID CLUSTERS
SULFUR