Premium
A precise and accurate method of measuring Kendrew model coordinates
Author(s) -
Frentrup M. A.,
Tulinsky A.
Publication year - 1981
Publication title -
journal of applied crystallography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.429
H-Index - 162
ISSN - 1600-5767
DOI - 10.1107/s0021889881009722
Subject(s) - standard deviation , polar coordinate system , dimer , chemistry , absolute deviation , dihedral angle , polar , bipolar coordinates , log polar coordinates , orthogonal coordinates , molecule , mathematical analysis , physics , hydrogen bond , mathematics , geometry , nuclear magnetic resonance , statistics , organic chemistry , astronomy
Polar coordinates of a Kendrew model of α‐chymotrypsin (α‐CHT) have been measured with a surveyor's transit and a cathetometer to a high degree of accuracy and precision. Bond distances calculated independently for more than 200 independent amino‐acid residues have standard deviations of 0.10 Å or less, the torsion angle ω has a standard error of 7°, and the τ angle is precise to 3°. The measured coordinates of about 1800 non‐hydrogen atoms of one molecule of the α‐CHT dimer fit a set of idealized polypeptide coordinates with a r.m.s. deviation of 0.17 Å, while the average deviation is 0.15 Å.