Interaction between the left‐handed Z‐DNA and polyamine The crystal structure of the d(CG)₃ and N‐(2‐aminoethyl)‐1,4‐diamino‐butane complex

Abstract

The DNA fragment d(CG), was co-crystallized with N-(2-aminoethyl)-1,4-diaminobutanc (PA (24)

Interaction between the left‐handed Z‐DNA and polyamine‐2

“…The rotation angle of the glycosyl bond of the cytidine residues took the anti conformation and that of the guanosine residues was syn. The rotation angle around the P9 phosphate was the standard Z-I type (-sc/-sc), while in the case of the d(CG)3-PA(24) complex, that was the unusual Z-II type (ap/+sc) [1].…”

“…We recently reported the crystal structure of the le•handed Z-DNA, d(CG)3, and N-(2-aminoethyl)-l,4-diamino-butane [PA(24)] complex [1], in which the PA(24) molecule hydrogen-bonded tightly to the minor groove of d(CG)3 and the sodium and the magnesium cations played an important role in the complex stabilization. It is well known that polyamine derivatives are essential for promoting cell growth, for inducing the biosynthesis of DNA, RNA and proteins [2], and for regulating the various enzyme activities in vitro [3].…”

Structure of d(TGCGCA)2 and a Comparison to Other DNA Hexamers

“…The ®rst structure obtained was d(CGCGCG) 2 (Wang et al, 1979) and since then variations including both alternating pyrimidine±purine (Wang, Hakoshima et al, 1984;Zhou & Ho, 1990;Sadasivan & Gautham, 1995) and non-alternating sequences Schroth et al, 1993) have been determined. The d(CGCGCG) 2 Z-DNA hexamer has also been used as a duplex framework for high-resolution studies of nonWatson±Crick mismatched base pairs (Brown et al, 1986) and modi®ed base-pairing geometries (Coll et al, 1989;Ginell et al, 1990;van Meervelt et al, 1990;Ohishi et al, 1991;Cervi et al, 1993;Moore et al, 1995). It has been proposed that the Z-DNA conformation is stabilized by methylation of cytosine (Fujii et al, 1982) and demethylation of thymine (Zhou & Ho, 1990).…”

“…Polyvalent metals are usually necessary to stabilize Z-DNA and cobalt hexammine is known to be particularly effective (Behe & Felsenfeld, 1981). The structural role of metal stabilization of Z-DNA has been explored in several structures containing Mg 2+ (Bancroft et al, 1994;Egli et al, 1991;Ohishi et al, 1991Ohishi et al, , 1996 and one containing cobalt hexammine .…”

Interaction between left‐handed Z‐DNA and polyamine — 3 The crystal structure of the d(CG)3 and thermospermine complex

“…Recently, we reported the crystal structures of the lefthanded Z-DNA fragment, d(CG)3, in complexes with N-(2-aminoethyl)-l,4-diaminobutane (PA(24)) [1], and with N-(2-aminopropyl)-l,4-diaminobutane (spermidine, PA(34)) [2], and discussed the mode of interaction of these complexes [3]. On the other hand, the structure of the d(CGh+spermine complex was determined by Wang et al [4].…”