International
Tables for
Crystallography
Volume F
Crystallography of biological macromolecules
Edited by M. G. Rossmann and E. Arnold

© International Union of Crystallography 2006
International Tables for Crystallography (2006). Vol. F. ch. 23.3, p. 608   | 1 | 2 |

Figure 23.3.4.9 

R. E. Dickersona*

a Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095–1570, USA
Correspondence e-mail: red@mbi.ucla.edu

[Figure 23.3.4.9]
Figure 23.3.4.9

Slide versus roll plots for six of the ten possible base-pair steps. Data points are from 971 steps in crystal structure analyses of 63 sequence-specific protein–DNA complexes. A complete set of 30 plots for slide/roll, twist/roll and slide/twist at all ten steps is to be found in Dickerson (1998b)[link], and equivalent plots for DNA alone are given by El Hassan & Calladine (1997)[link]. Y-R steps exhibit a broad range of roll, slide and twist values, with roughly linear correlations between pairs of variables. Points for A-A and other R-R steps cluster tightly around the origin, showing little tendency toward roll bending. Curiously enough, points for R-Y steps tend to favour negative values of slide and twist, and, hence, to concentrate in the lower left quadrant of a slide/tilt plot.