Three-dimensional solution structure of Ca sup 2+ -loaded porcine calbindin D sub 9k determined by nuclear magnetic resonance spectroscopy

Journal Article · Tue Feb 04 04:00:00 EST 1992 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00119a009· OSTI ID:5559845

Akke, M; Drakenberg, T; Chazin, W J ^[1]

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1. Scripps Research Inst., La Jolla, CA (United States)

The three-dimensional solution structure of native, intact porcine calbindin D{sub 9k} has been determined by distance geometry and restrained molecular dynamics calculations using distance and dihedral angle constraints obtained from {sup 1}H NMR spectroscopy. The protein has a well-defined global fold consisting of four helices oriented in a pairwise antiparallel manner such that two pairs of helix-loop-helix motifs (EF-hands) are joined by a linker segment. The two EF-hands are further coupled through a short {beta}-type interaction between the two Ca{sup 2+}-binding loops. Overall, the structure is very similar to that of the highly homologous native, minor A form of bovine calbindin D{sub 9k} determined by X-ray crystallography. A model structure built from the bovine calbindin D{sub 9k} crystal structure shows several deviations larger than 2 {angstrom} from the experimental distance constraints for the porcine protein. These structural differences are efficiently removed by subjecting the model structure to the experimental distance and dihedral angle constraints in a restrained molecular dynamics protocol, thereby generating a model that is very similar to the refined distance geometry derived structures. The N-terminal residues of the intact protein that are absent in the minor A form appear to be highly flexible and do not influence the structure of other regions of the protein. This result is important because in validates the conclusions drawn from the wide range of studies that have been carried out on minor A forms rather than the intact calbindin D{sub 9k}.

• OSTI ID: 5559845
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 31:4; ISSN 0006-2960; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALINE EARTH METAL COMPOUNDS
AMIDES
AMINO ACIDS
ANIMALS
AQUEOUS SOLUTIONS
ASPARAGINE
CALCIUM COMPOUNDS
CALMODULIN
CARBOXYLIC ACIDS
COHERENT SCATTERING
CRYSTALLOGRAPHY
DIFFRACTION
DISPERSIONS
DOMESTIC ANIMALS
GEOMETRY
MAGNETIC RESONANCE
MAMMALS
MATHEMATICS
MIXTURES
NUCLEAR MAGNETIC RESONANCE
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PROTEINS
RESONANCE
SCATTERING
SOLUTIONS
SWINE
VERTEBRATES
X-RAY DIFFRACTION