X-ray absorption studies of metalloprotein structure: cytochrome P-450, horseradish peroxidase, plastocyanin and laccase

Technical Report · Wed Feb 29 23:00:00 EST 1984

OSTI ID:6975764

Penner-Hahn, J E

Extended x-ray absorption fine structure (EXAFS) has been developed to determine the structure of metalloproteins. EXAFS data have been collected and analysed for four states in the catalytic cycle of bacterial cytochrome P-450/sub CAM/. This data demonstrates that sulfur is retained as an axial ligand in the reduced forms of the enzyme. EXAFS and edge data have been analysed for the high-valent states of horseradish peroxidase (HRP), and for high-valent iron-porphyrin model compounds. These data provide the first direct confirmation of the presence of a ferryl Fe=O coordination in HRP and in some of the model compounds. The polarized single-crystal EXAFS spectra of plastocyanin have been measured as a function of both orientation and temperature. These data demonstrate that at room temperature the relative motions of the Cu and the S(Met) are essentially uncorrelated.

• Research Organization: Stanford Univ., CA (USA). Stanford Synchrotron Radiation Lab.
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 6975764
• Report Number(s): SSRL-84/03; ON: DE84011318
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
BIOCHEMICAL REACTION KINETICS
CARBOXYLIC ACIDS
COPPER COMPOUNDS
CYTOCHROMES
ENZYMES
FOURIER TRANSFORMATION
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
INTEGRAL TRANSFORMATIONS
KINETICS
MOLECULAR STRUCTURE
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDOREDUCTASES
OXYGENASES
PEROXIDASES
PIGMENTS
PORPHYRINS
REACTION KINETICS
SPECTROSCOPY
TRANSFORMATIONS
TRANSITION ELEMENT COMPOUNDS
VALENCE
X-RAY SPECTROSCOPY