Abstract
Studies have been made of conformational parameters in co-crystal complexes and compounds of nucleic acid bases in which there is the possibility of formation of hetero-base-pairs. Using published data extracted from the Cambridge structural database, a total of 37 base-pairs were found, of which 25 were hetero-pairs and 12 homo-pairs. These base-pairs were subject to analysis to reveal hydrogen bond parameters, propeller twist, buckle and C1'-C1' separation (or a similar parameter if C1' atoms were not present). Hetero-pairs were found to show larger twists than homo-pairs, the magnitude of twist being unrelated to hydrogen bond parameters or buckle value. The propeller twisting is less pronounced in these nucleic acid bases than in nucleosides, but still has a significant magnitude. Propeller twisting in hetero-pairs is found to be larger than in homo-pairs. Hetero-pairs appear to be formed preferentially in competitive situations.
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- Dickerson R. E. Base sequence and helix structure variation in B and A DNA. J Mol Biol. 1983 May 25;166(3):419–441. doi: 10.1016/s0022-2836(83)80093-x. [DOI] [PubMed] [Google Scholar]
- Mazza F., Sobell H. M., Kartha G. Base-pairing configurations between purines and pyrimidines in the solid state. IV. Crystal and molecular structure of two 1:1 hydrogen-bonded complexes, 1-methyl-5-bromouracil: 9-ethyl-2-aminopurine and 1-methyl-5-fluorouracil: 9-ethyl-2-aminopurine. J Mol Biol. 1969 Aug 14;43(3):407–422. doi: 10.1016/0022-2836(69)90349-0. [DOI] [PubMed] [Google Scholar]
- Mazza F., Sobell H. M., Kartha G. Base-pairing configurations between purines and pyrimidines in the solid state. IV. Crystal and molecular structure of two 1:1 hydrogen-bonded complexes, 1-methyl-5-bromouracil: 9-ethyl-2-aminopurine and 1-methyl-5-fluorouracil: 9-ethyl-2-aminopurine. J Mol Biol. 1969 Aug 14;43(3):407–422. doi: 10.1016/0022-2836(69)90349-0. [DOI] [PubMed] [Google Scholar]
- Sakore T. D., Sobell H. M., Mazza F., Kartha G. Base-pairing configurations between purines and pyrimidines in the solid state. 3. Crystal and molecular structure of two 2:1 hydrogen-bonded complexes, 1-methylthymine: 9-ethyl-2,6-diaminopurine and 1-methyl-5-iodouracil: 9-ethyl-2,6-diaminopurine. J Mol Biol. 1969 Aug 14;43(3):385–406. doi: 10.1016/0022-2836(69)90348-9. [DOI] [PubMed] [Google Scholar]
- Sakore T. D., Tavale S. S., Sobell H. M. Base-pairing configurations between purines and pyrimidines in the solid state. I. Crystal and molecular structure of a 1:2 purine-pyrimidine hydrogen-bonded complex: 9-ethyladenine-1-methyl-5-iodouracil. J Mol Biol. 1969 Aug 14;43(3):361–374. doi: 10.1016/0022-2836(69)90346-5. [DOI] [PubMed] [Google Scholar]
- Simundza G., Sakore T. D., Sobell H. M. Base-pairing configurations between purines and pyrimidines in the solid state. V. Crystal and molecular structure of two 1:1 hydrogen-bonded complexes, 1-methyluracil: 9-ethyl-8-bromo-2,6-diaminopurine and 1-ethylthymine: 9-ethyl-8-bromo-2,6--diaminopurine. J Mol Biol. 1970 Mar 14;48(2):263–278. doi: 10.1016/0022-2836(70)90160-9. [DOI] [PubMed] [Google Scholar]
- Tavale S. S., Sakore T. D., Sobell H. M. Base-pairing configurations between purines and pyrimidines in the solid state. II. Crystal and molecular structure of 9-ethyl-8-bromoadenine-1-methyl-5-bromouracil. J Mol Biol. 1969 Aug 14;43(3):375–384. doi: 10.1016/0022-2836(69)90347-7. [DOI] [PubMed] [Google Scholar]
- Tomita K., Katz L., Rich A. Crystal structure of the intermolecular complex 9-ethyladenine: 1-methyl-5-fluorouracil. J Mol Biol. 1967 Dec 28;30(3):545–549. doi: 10.1016/0022-2836(67)90367-1. [DOI] [PubMed] [Google Scholar]