Evidence for A+(anti)-G(syn) mismatched base-pairing in d-GGTAAGCGTACC.
Two-dimensional NMR spectroscopy has been used to study the structure and hydrogen bonding scheme of A:G mismatched base pairing in d-GGTAAGCGTACC at pH 5.8. Under the conditions of our study, the molecule forms a B-DNA helix, with the mismatched bases in the A+ anti)-G(syn) conformation. The adenosine exists in the protonated form. The NOESY spectrum in 90% H2O + 10% 2H2O has been used to assign all observable imino and amino protons including those involved in the A+(anti)-G(syn) base pair. Both the proton donors in the A:G mismatched inter-base hydrogen bonding are situated on adenosine.
Chemical Physics Group, Tata Institute of Fundamental Research, Bombay, India.
A K
AK
Sau
K V
KV
Chary
G
G
Govil
C Q
CQ
Chen
F B
FB
Howard
H T
HT
Miles
D001482:Base Composition; D001483:Base Sequence; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D003838:Deoxyadenine Nucleotides / Q000737:chemistry; D003848:Deoxyguanine Nucleotides / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry*
D003838:Deoxyadenine Nucleotides; D003848:Deoxyguanine Nucleotides; D009838:Oligodeoxyribonucleotides; D004247:DNA