| THE COORDINATES ARE NUMBERED AS FOLLOWS:
SUBUNIT 1: 1-101.
SUBUNIT 2: 201-301.
THE DIMER IS FULLY SYMMETRIC.
THE AB' HALF OF THE DIMER COMPRISES RESIDUES 1-48 and 255-301.
THE A'B HALF OF THE DIMER COMPRISES RESIDUES 201-248 and 55-101.
THE COORDINATES OF THE TWO HALVES OF THE DIMER ARE TAKEN FROM
THE X-RAY COORDINATES (3EZM, 1.5 A RESOLUTION).
THE ORIENTATION OF THE AB' HALF OF THE DIMER
(RESIDUES 1-48 AND 255-301)
RELATIVE TO THE A'B HALF OF THE DIMER (RESIDUES 201-248 AND
55-101) ARE DETERMINED BY CONJOINED RIGID BODY/TORSION ANGLE
DYNAMICS ON THE BASIS OF RESIDUAL DIPOLAR COUPLINGS (68 x 2),
ALLOWING ONLY THE PHI/PSI TORSION ANGLES OF RESIDUES 49-54
AND 249-254 TO ALTER THEIR CONFORMATION (SUBJECT TO
NON-CRYSTALLOGRAPHIC SYMMETRY). IN ADDITION TO TERMS
FOR DIPOLAR COUPLINGS (CLORE ET AL. J.MAGN.RESON. 131, 159-162
(1998) AND NON-CRYSTALLOGRAPHIC SYMMETRY,
THE TARGET FUNCTION ALSO INCLUDES A TERM OF A TORSION ANGLE
DATABASE POTENTIAL OF MEAN FORCE (KUSZEWSKI AND CLORE,
J. MAGN. RESON 146, 249-254 (2000)).
DATA USED IN REFINEMENT:
68 x 2 1DNH DIPOLAR COUPLINGS MEASURED IN 5% C12E5 POLYETHYLENE
GLYCOL/HEXANOL MIXTURE WITH A MOLAR RATIO OF SURFACTANT TO
ALCOHOL OF 0.96 (PEG).
AGREEMENT WITH EXPERIMENTAL DATA:
DIPOLAR COUPLING R-FACTOR (CLORE AND GARRETT (1999)
J. AM. CHEM. SOC. 121, 9008-9012):
R-DIPOLAR (WORK/PEG) (68 x 2 COUPLINGS): 14.2%
R-DIPOLAR (FREE/BICELLES) (18 x 2 COUPLINGS): 15.3%
(CROSS-VALIDATED).
(FOR REFERENCE, THE VALUES OF R-DIPOLAR IN PEG AND BICELLES
FOR THE ORIENTATION OF THE TWO-HALVES OF THE DOMAIN-SWAPPED
DIMER IN THE X-RAY COORDINATES, 3EZM, ARE 55.9% and 56.6%,
RESPECTIVELY).
The only protons in the coordinates are the backbone amide
protons and the Ne1H proton of Trp. Note the coordinates for
the two halves of the domain-swapped dimer are taken directly
from the X-ray coordinates (3EZM) and their relative orientation
is determined only on the basis of N-H dipolar couplings. Hence,
there was no need to add the other protons to the coordinates.
IN THIS ENTRY, THE LAST COLUMN REPRESENTS THE AVERAGE RMS
DIFFERENCE BETWEEN THE INDIVIDUAL SIMULATED ANNEALING STRUCTURES
(20) AND THE MEAN COORDINATE POSITIONS. BEST FITTING TO GENERATE
THE AVERAGE STRUCTURE IS WITH RESPECT TO RESIDUES 1-101 AND
201-301. NOTE THESE ERRORS ONLY REFLECT THE PRECISION WITH
WHICH THE RELATIVE ORIENTATION OF THE TWO HALVES OF THE
DOMAIN-SWAPPED DIMER HAS BEEN DETERMINED RELATIVE TO EACH OTHER.
THEY DO NOT REFLECT THE ERRORS IN THE X-RAY COORDINATES OF 3EZM
(WHICH ARE AROUND 0.09-0.16 A).
NOTE THE OCCUPANCY FIELD HAS NO MEANING. | X-PLOR-NIH |
