The orientation of CO in carbonmonoxy cytochrome oxidase and its transient photoproducts. Direct evidence from time-resolved infrared linear dichroism

Journal Article · Wed Nov 22 00:00:00 EST 1989 · Journal of the American Chemical Society; (USA)

DOI:https://doi.org/10.1021/ja00206a053· OSTI ID:6971139

Dyer, R B; Lopez-Garriga, J J; Einarsdottir, O; Woodruff, W H ^[1]

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1. Los Alamos National Lab., NM (USA)

Cytochrome oxidase (cytochrome aa{sub 3} or CcO) mediates the facile reduction of O{sub 2} by cytochrome c in all plants and animals and numerous lower organisms and conserves the energy of this reaction as a transmembrane proton gradient. The crucial early steps in the activation of O{sub 2} involve its binding to the heme/copper site, denoted cytochrome a{sub 3}/copper B. The coordination chemistry and structure of this site are essential, but poorly understood, functional features of the enzyme. In this report they have applied time-resolved infrared linear dichroism (TRIRLID) to the CO complex of fully reduced CcO from bovine heart and have measured directly the orientation of the C-O bond axis with respect to the heme normal of cytochrome a{sub 3}, both in Fe{sub a3}{sup 2+}-CO and in the Cu{sub B}{sup +}-CO phototransient.

• OSTI ID: 6971139
• Journal Information: Journal of the American Chemical Society; (USA), Vol. 111:24; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
59 BASIC BIOLOGICAL SCIENCES
CYTOCHROMES
DICHROISM
CARBON MONOXIDE
DATA ANALYSIS
ENZYMES
EXPERIMENTAL DATA
INFRARED RADIATION
MEASURING INSTRUMENTS
MEASURING METHODS
OXYGEN
REDUCTION
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
DATA
ELECTROMAGNETIC RADIATION
ELEMENTS
INFORMATION
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PIGMENTS
PROTEINS
RADIATIONS
400500* - Photochemistry
550000 - Biomedical Sciences
Basic Studies