1d58
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THE MOLECULAR STRUCTURE OF A 4'-EPIADRIAMYCIN COMPLEX WITH D(TGATCA) AT 1.7 ANGSTROM RESOLUTION-COMPARISON WITH THE STRUCTURE OF 4'-EPIADRIAMYCIN D(TGTACA) AND D(CGATCG) COMPLEXES
OverviewOverview
The structure of the complex between d(TGATCA) and the anthracycline, 4'-epiadriamycin has been determined by crystallographic methods. The, crystals are tetragonal, space group P4(1)2(1)2 with unit cell dimensions, of a = 28.01, c = 52.95A. The asymmetric unit consists of one strand of, hexanucleotide, one molecule of 4'-epiadriamycin and 34 waters. The, R-factor is 20.2% for 1694 reflections with F greater than or equal to 2, sigma F to 1.7A. Two asymmetric units associate to generate a duplex, complexed with two drug molecules at the d(TpG) steps of the duplex. The, chromophore intercalates between these base pairs with the anthracycline, amino-sugar positioned in the minor groove. The double helix is a, distorted B-DNA type structure. Our structure determination of d(TGATCA), complexed to 4'-epiadriamycin allows for comparison with the previously, reported structures of 4'-epiadriamycin bound to d(TGTACA) and to, d(CGATCG). The three complexes are similar in gross features and the, intercalation geometry is the same irrespective of whether a d(CpG) or, d(TpG) sequence is involved. However, the orientation of the amino-sugar, displays a dependence on the sequence adjacent to the intercalation site., The flexibility of this amino-sugar may help explain why this class of, antibiotics displays a relative insensitivity to base sequence when they, bind to DNA.
About this StructureAbout this Structure
1D58 is a Protein complex structure of sequences from [1] with DM6 as ligand. Full crystallographic information is available from OCA.
ReferenceReference
The molecular structure of a 4'-epiadriamycin complex with d(TGATCA) at 1.7A resolution: comparison with the structure of 4'-epiadriamycin d(TGTACA) and d(CGATCG) complexes., Langlois d'Estaintot B, Gallois B, Brown T, Hunter WN, Nucleic Acids Res. 1992 Jul 25;20(14):3561-6. PMID:1641324
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