Three-dimensional solution structure of the reduced form of Escherichia coli thioredoxin determined by nuclear magnetic resonance spectroscopy

Journal Article · Tue May 01 04:00:00 EDT 1990 · Biochemistry; (USA)

DOI:https://doi.org/10.1021/bi00469a016· OSTI ID:6171646

Dyson, H J; Gippert, G P; Case, D A; Wright, P E ^[1]; Holmgren, A ^[2]

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1. Research Institute of Scripps Clinic, La Jolla, CA (USA)
2. Karolinska Institutet, Stockholm (Sweden)

The three-dimensional solution structure of reduced (dithiol) thioredoxin from Escherichia coli has been determined with distance and dihedral angle constraints obtained from {sup 1}H NMR spectroscopy. Reduced thioredoxin has a well-defined global fold consisting of a central five-strand {beta}-sheet and three long helices. The {beta}-strands are packed in the sheet in the order {beta}{sub 1}{beta}{sub 3}{beta}{sub 2}{beta}{sub 4}{beta}{sub 5}, with {beta}{sub 1}, {beta}{sub 3}, and {beta}{sub 2} parallel and {beta}{sub 2}, {beta}{sub 4}, and {beta}{sub 5} arranged in an antiparallel fashion. Two of the helices connect strands of the {beta}-sheet: {alpha}{sub 1} between {beta}{sub 1} and {beta}{sub 2} and {alpha}{sub 2} between {beta}{sub 2} and {beta}{sub 3}. Strands {beta}{sub 4} and {beta}{sub 5} are connected by a short loop that contains a {beta}-bulge. Strands {beta}{sub 3} and {beta}{sub 4} are connected by a long loop that contains a series of turn-like or 3{sub 10} helical structures. The active site Cys-Gly-Pro-Cys sequence forms a protruding loop between strand {beta}{sub 2} and helix {alpha}{sub 2}. The structure is very similar overall to that of oxidized (disulfide) thioredoxin obtained from X-ray crystal structure analysis but differs in the local conformation of the active site loop. The distance between the sulfurs of Cys 32 and Cys 35 increases from 2.05 {angstrom} in the disulfide bridge to 6.8 {plus minus} 0.6 {angstrom} in the dithiol of reduced thioredoxin, as a result of a rotation of the side chain of Cys 35 and a significant change in the position of Pro 34. This conformational change has important implications for the mechanism of thioredoxin as a protein disulfide oxidoreductase.

• OSTI ID: 6171646
• Journal Information: Biochemistry; (USA), Journal Name: Biochemistry; (USA) Vol. 29:17; ISSN 0006-2960; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINES
AMINO ACIDS
AZOLES
BACTERIA
BARYONS
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CONFORMATIONAL CHANGES
CYSTEINE
ELEMENTARY PARTICLES
ENZYMES
ESCHERICHIA COLI
FERMIONS
GLYCINE
HADRONS
HEAVY WATER
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
MAGNETIC RESONANCE
MICROORGANISMS
MOLECULAR STRUCTURE
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUCLEONS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
OXIDOREDUCTASES
OXYGEN COMPOUNDS
PROLINE
PROTONS
PYRROLES
PYRROLIDINES
RESONANCE
SPECTRA
THIOLS
WATER