title: Circular dichroism of adenosine dinucleotides.
abstract: The circular dichroism and absorption spectra of (3'-5')ApA, (5'-5')AppA, and (5'-5')ApcpA [diadenosine(5'5') pyrophosphonate] under various ionic coditions and at various temperatures are reported. Temperature studies reveal that under the same ionic strength and solvation conditions the probability of base-base interaction is ApA greater than AppA greater than ApcpA. It is found that increasing the molar refractivity of the solvent decreases the base-base interaction for both ApA and AppA and that both compounds proceed to a monomeric state in solvents of high molar refractivity. Solvent effect studies also indicate that a major percentage of the driving force for the base-base interaction can be accounted for by London dispersion forces. Low ionic strength appears to favor the base-base interacted conformation. All compounds tend toward the same noninteracted form at high temperatures. Plots of [theta]lambda against X (where X is an experimental parameter) were constructed in order to obtain information concerning which transitions might be undergoing oscillator coupling. To a first approximation, transitions coupled to each other should have very similar deta[theta]lambda/detaX for the experimental range of X. Applying this technique to the experimental data yielded information concerning possible transition coupling.
mesh_terms: D000227:Adenine Nucleotides; D002942:Circular Dichroism; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides; D009843:Oligoribonucleotides; D009994:Osmolar Concentration; D012997:Solvents; D013696:Temperature
chemical_list: D000227:Adenine Nucleotides; D009841:Oligonucleotides; D009843:Oligoribonucleotides; D012997:Solvents
references.citation: Biochem Biophys Res Commun. 1965 Feb 17;18:633-8
references.pmid: 14301471
references.citation: Annu Rev Biochem. 1975;44:725-74
references.pmid: 1094921
references.citation: Biochim Biophys Acta. 1974 Mar 27;340(3):299-313
references.pmid: 4826257
references.citation: J Mol Biol. 1972 Mar 14;65(1):91-109
references.pmid: 5019219
references.citation: Nat New Biol. 1972 Mar 22;236(64):67-70
references.pmid: 4502454
references.citation: Prog Nucleic Acid Res Mol Biol. 1969;9:327-402
references.pmid: 4305447
references.citation: J Biol Chem. 1968 Aug 25;243(16):4181-8
references.pmid: 4300549
references.citation: Biochemistry. 1972 Dec 5;11(25):4811-7
references.pmid: 4632121
references.citation: Biopolymers. 1974;13(2):345-57
references.pmid: 4594851
references.citation: Biopolymers. 1974;13(7):1391-403
references.pmid: 4412286
references.citation: Biopolymers. 1974;13(7):1377-89
references.pmid: 4412285
references.citation: Biopolymers. 1974;13(7):1405-16
references.pmid: 4412284
references.citation: Biopolymers. 1974 May;13(5):863-77
references.pmid: 4854448
references.citation: Biopolymers. 1974 May;13(5):977-86
references.pmid: 4851435
references.citation: Biochem Biophys Res Commun. 1974 Jul 24;59(2):672-9
references.pmid: 4859561
references.citation: Biopolymers. 1974;13(2):339-44
references.pmid: 4820065
references.citation: Biopolymers. 1974;13(2):289-306
references.pmid: 4820062
references.citation: Biopolymers. 1974;13(2):241-55
references.pmid: 4820059
references.citation: Biopolymers. 1973 Dec;12(12):2777-88
references.pmid: 4782553
references.citation: Biopolymers. 1973 Nov;12(11):2459-75
references.pmid: 4780713
references.citation: Biopolymers. 1973;12(1):89-110
references.pmid: 4687151
references.citation: Biopolymers. 1973;12(1):201-21
references.pmid: 4687148
references.citation: Biopolymers. 1973;12(1):1-10
references.pmid: 4687147
references.citation: J Am Chem Soc. 1973 May 2;95(9):2803-13
references.pmid: 4694713
references.citation: Biopolymers. 1973 May;12(5):1098-122
references.pmid: 4710250
references.citation: Biochem Biophys Res Commun. 1972 Jun 28;47(6):1284-9
references.pmid: 5040235
references.citation: Biopolymers. 1972 Jan;11(1):235-50
references.pmid: 5008183
references.citation: Biopolymers. 1972 Jan;11(1):225-34
references.pmid: 5008182
references.citation: Prog Nucleic Acid Res Mol Biol. 1969;9:223-300
references.pmid: 4888948
references.citation: Proc Natl Acad Sci U S A. 1967 May;57(5):1138-45
references.pmid: 5231724
references.citation: Proc Natl Acad Sci U S A. 1965 Aug;54(2):640-8
references.pmid: 5217450
references.citation: Biochemistry. 1968 Aug;7(8):2791-9
references.pmid: 5666752
references.citation: J Phys Chem. 1967 Dec;71(13):4448-54
references.pmid: 6075615
references.citation: J Mol Biol. 1967 Feb 14;23(3):601-4
references.pmid: 6032193
references.citation: J Mol Biol. 1965 Jul;12(3):726-39
references.pmid: 5858431