title: An investigation into the solution structures of two self-complementary DNA oligomers, 5'-d(C-G-T-A-C-G) and 5'-d(A-C-G-C-G-C-G-T), by means of nuclear-Overhauser-enhancement measurements.
abstract: A 500 MHz 1H-n.m.r. study on two self-complementary alternating pyrimidine-purine oligodeoxyribonucleotides, 5'-d(C-G-T-A-C-G) and 5'-d(A-C-G-C-G-C-G-T), is presented. By using the proton-proton nuclear Overhauser effect virtually complete assignments are obtained and a large number of interproton distances [113 in the case of 5'-d(C-G-T-A-C-G) and 79 in the case of 5'-d(A-C-G-C-G-C-G-T)], both intra- and inter-nucleotide, are determined. The interproton-distance data are consistent with an overall right-handed B-DNA-type structure for both oligonucleotides, in agreement with their B-type c.d. spectra. However, whereas 5'-d(C-G-T-A-C-G) adopts a conventional B-type structure with a mononucleotide repeating unit, the interproton-distance data provide evidence that 5'-d(A-C-G-C-G-C-G-T) has a dinucleotide repeating unit consisting of alternation in glycosidic bond and sugar pucker conformations.
mesh_terms: D001482:Base Composition; D004247:DNA; D009682:Magnetic Resonance Spectroscopy; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides
chemical_list: D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides; D004247:DNA