THREE-DIMENSIONAL SOLUTION STRUCTURE OF HUMAN INTERLEUKIN-4 BY MULTI-DIMENSIONAL HETERONUCLEAR MAGNETIC RESONANCE SPECTROSCOPY
Three-dimensional solution structure of human interleukin-4 by multidimensional heteronuclear magnetic resonance spectroscopy.
1H, 15N, 13C and 13Co Assignments of Human Interleukin-4 Using Three-Dimensional Double-and Triple-Resonance Heteronuclear Magnetic Resonance Spectroscopy
Determination of the Secondary Structure and Folding Topology of Human Interleukin-4 Using Three-Dimensional Heteronuclear Magnetic Resonance Spectroscopy
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THE NUMBERING SCHEME IN THIS STRUCTURE INCLUDES THE FOUR-RESIDUE SEQUENCE GLU-ALA-GLU-ALA AT THE N-TERMINUS OF THE RECOMBINANT PROTEIN WHICH IS NOT PART OF THE NATURAL HUMAN IL-4; THE NATURAL IL-4 SEQUENCE THEREFORE STARTS AT RESIDUE 5. IN ADDITION, THE TWO POTENTIAL N-LINKED GLYCOSYLATION SITES AT ASN 42 AND ASN 109 HAVE BEEN CHANGED TO ASP BY SITE DIRECTED MUTAGENESIS TO PREVENT HYPERGLYCOSYLATION IN THE YEAST HOST.
DETAILS OF THE STRUCTURE DETERMINATION AND ALL STRUCTURAL STATISTICS ARE GIVEN IN REFERENCE 1 (I.E. AGREEMENT WITH EXPERIMENTAL RESTRAINTS, DEVIATIONS FROM IDEALITY FOR BOND LENGTHS, ANGLES, PLANES AND CHIRALITY, NON-BONDED CONTACTS, ATOMIC RMS DIFFERENCES BETWEEN THE CALCULATED STRUCTURES. THE STRUCTURES ARE BASED ON 823 INTERPROTON DISTANCE RESTRAINTS FROM NOE MEASUREMENTS; 98 HYDROGEN-BONDING DISTANCE RESTRAINTS FOR 49 HYDROGEN-BONDS IDENTIFIED ON THE BASIS OF THE NOE AND AMIDE PROTON EXCHANGE DATA, AS WELL AS THE INITIAL STRUCTURE CALCULATIONS; AND 101 PHI AND 82 PSI BACKBONE TORSION ANGLE RESTRAINTS DERIVED FROM COUPLING CONSTANTS, NOE DATA, AND 13C SECONDARY CHEMICAL SHIFTS. THE METHOD USED TO DETERMINE THE STRUCTURES IS THE HYBRID METRIC MATRIX DISTANCE GEOMETRY-DYNAMICAL SIMULATED ANNEALING METHOD (M. NILGES, G. M. CLORE, AND A. M. GRONENBORN FEBS LETT. 229, 317-324 (1988)). RESIDUES 1 - 6 AND 132 - 133 AT THE N- AND C-TERMINI ARE DISORDERED. THE RESTRAINED MINIMIZED AVERAGE STRUCTURE IS PRESENTED IN PROTEIN DATA BANK ENTRY 1BBN. THIS WAS OBTAINED BY AVERAGING THE COORDINATES OF THE INDIVIDUAL STRUCTURES AND SUBJECTING THE RESULTING COORDINATES TO RESTRAINED MINIMIZATION. MODELS 1 - 22, PRESENTED IN THIS ENTRY, REPRESENT THE INDIVIDUAL MODELS. THE (SA)R RESTRAINED MINIMIZED MEAN STRUCTURE WAS DERIVED BY AVERAGING THE COORDINATES OF THE INDIVIDUAL SA STRUCTURES (BEST FITTED TO RESIDUES 7 - 131), AND SUBJECTING THE RESULTING COORDINATES TO RESTRAINED MINIMIZATION. THE QUANTITY PRESENTED IN COLUMNS 61 - 66 IN ENTRY 1BBN REPRESENTS THE ATOMIC RMS DEVIATIONS OF THE 22 INDIVIDUAL SA STRUCTURES ABOUT THE MEAN STRUCTURE.
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