TY - JOUR
T1 - Base stacking and molecular polarizability
T2 - Effect of a methyl group in the 5-position of pyrimidines
AU - Sowers, Lawrence C.
AU - Shaw, Barbara Ramsay
AU - Sedwick, W. David
PY - 1987/10/29
Y1 - 1987/10/29
N2 - Substitution of a methyl group in the 5-position of pyrimidines increases melting temperatures and modifies biological properties of DNA. Increased DNA stability is often attributed to hydrophobic interactions between water and the methyl group. However, we present evidence that the major effect of methyl substitution is to increase the molecular polarizability of the pyrimidine, thereby increasing the base stacking. Experimentally determined base stacking interaction constants for free bases in water are shown to correlate well with calculated molecular polarizability and DNA melting temperatures.
AB - Substitution of a methyl group in the 5-position of pyrimidines increases melting temperatures and modifies biological properties of DNA. Increased DNA stability is often attributed to hydrophobic interactions between water and the methyl group. However, we present evidence that the major effect of methyl substitution is to increase the molecular polarizability of the pyrimidine, thereby increasing the base stacking. Experimentally determined base stacking interaction constants for free bases in water are shown to correlate well with calculated molecular polarizability and DNA melting temperatures.
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U2 - 10.1016/0006-291X(87)90945-4
DO - 10.1016/0006-291X(87)90945-4
M3 - Article
C2 - 3689373
AN - SCOPUS:0023667625
SN - 0006-291X
VL - 148
SP - 790
EP - 794
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 2
ER -