Factoring of the hyperfine shifts in the cyanide adduct of lignin peroxidase from P. chrysosporium

Journal Article · Wed Aug 23 04:00:00 EDT 1995 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/ja00138a023· OSTI ID:102736

Banci, L; Bertini, I; Pierattelli, R ^[1]; Tien, M ^[2]; Vila, A J ^[3]

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1. Univ. of Florence (Italy)
2. Pennsylvania State Univ., University Park, PA (United States)
3. Universidad Nacional de Rosario (Argentina)

We have used NMR spectroscopy to study the cyanide derivative of lignin peroxidase with the goal of characterizing the electronic structure of this derivative of peroxidases. By using varions homonuclear and heteronuclear 2D NMR techniques and by making use of the available X-ray structure of the cyanide-free protein, it has been possible to extend the assignment of the heme substituents and of the protons of some active-site residues. An estimate of the anisotropy and direction of the magnetic susceptibility anisotropy tensor has been obtained from the pseudocontact shifts of protons of residues not directly bound to the heme iron ion. Finally, a factoring of the hyperfine shifts of the heme and proximal histidine protons, as well as of the {sup 13}C heme methyls and {sup 15}N of the cyanide moiety, is obtained. The contact shift pattern of the heme protons is related to the orientation of the histidine plane. Very large upfield contact shifts are experienced by the aromatic protons of the proximal histidine. The axial magnetic anisotropy is smaller than in metmyoglobin-CN and slightly larger than in horseradish peroxidase-CN. This may reflect the order of the donor strength of the proximal histidine. The z axis of the magnetic susceptibility tensor is found essentially perpendicular to the heme plane. 96 refs., 7 figs., 3 tabs.

• Sponsoring Organization: USDOE
• DOE Contract Number: FG02-87ER13690
• OSTI ID: 102736
• Journal Information: Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 33 Vol. 117; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
55 BIOLOGY AND MEDICINE
BASIC STUDIES
66 PHYSICS
ADDUCTS
CHEMICAL SHIFT
CYANIDES
ELECTRONIC STRUCTURE
HISTIDINE
LIGNIN
NMR SPECTRA
PEROXIDASES
SPECTRAL SHIFT