Analysis of. phi. and. chi. sub 1 torsion angles for hen lysozyme in solution from sup 1 H NMR spin-spin coupling constants

Journal Article · Tue Jan 29 00:00:00 EST 1991 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00218a015· OSTI ID:5398998

Smith, L J; Sutcliffe, M J; Redfield, C; Dobson, C M ^[1]

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1. Univ. of Oxford (England)

Three-bond {sup 3}J{sub HN{alpha}} coupling constants have been determined for 106 residues and {sup 3}J{sub {alpha}{beta}} coupling constants have been measured for 57 residues of the 129-residue protein hen egg white lysozyme. These NMR data have been compared with torsion angles defined in the tetragonal and the triclinic crystal forms of the protein. For most residues the measured {sup 3}J{sub HN{alpha}} values were consistent with the {phi} torsion angles found in both crystal forms; the RMS difference between the coupling constants calculated by using the tetragonal crystal structure {phi} angles and the experimental {sup 3}J{sub HN{alpha}} values is 0.88 Hz. Thus there appears to be no significant averaging of the {phi} torsion angle either in the interior or at the surface of the protein. For 41 of the residues where {sup 3}J{sub {alpha}{beta}} coupling constants have been determined, the values are consistent with a single staggered conformation about the {chi}{sub 1} torsion angle and there is complete agreement between the NMR data in solution and the torsion angles defined in the crystalline state. In contrast, for the other 16 residues where {sup 3}J{sub {alpha}{beta}} coupling constant values have been measured, the data indicate extensive motional averaging about the {chi}{sub 1} torsion angle. These residues occur largely on the surface of the protein and examination of the crystal structures shows that many of these residues adopt a different conformation in the triclinic and tetragonal crystal forms and have high crystallographic temperature factors. It appears, however, that in solution conformational flexibility of the side chains of surface residues is significantly more pronounced than in individual crystal structures.

• OSTI ID: 5398998
• Journal Information: Biochemistry; (United States), Vol. 30:4; ISSN 0006-2960
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
LYSOZYME
NUCLEAR MAGNETIC RESONANCE
CHICKENS
CONFORMATIONAL CHANGES
CRYSTALLOGRAPHY
EGGS
PROTONS
SPIN-SPIN RELAXATION
STEREOCHEMISTRY
ANIMALS
BARYONS
BIRDS
ELEMENTARY PARTICLES
ENZYMES
FERMIONS
FOWL
GLYCOSYL HYDROLASES
HADRONS
HYDROLASES
MAGNETIC RESONANCE
NUCLEONS
O-GLYCOSYL HYDROLASES
RELAXATION
RESONANCE
VERTEBRATES
550201* - Biochemistry- Tracer Techniques