CG doublets

CG doublets. The only modified base commonly found in eukaryotes is 5-methylcytosine,222/223 which upon deamination becomes thymine (Eq. 27-1). Most methylation occurs when C is followed by G. Usually 60-90% of all 5 -CG sequences (CpG sequences) in eukaryotic DNA are methylated. However, the fraction of methylated cytosine varies from almost zero for Drosophilia, Caenorhabditis, and Saccharomyces to as much as 30% in higher plants.224... 

The degree of methylation of the CG doublets is variable both in position within a chromosome and... 

Figure. 6. MEP for the two lowest doublet PES s of the A", A states calculated without contribution of S-O interaction energies are given in kcal/mol curves 1-5 are for linear (Y=0) MEP at long distances R curves 6-9 are for non-linear MEP at short distances solid curves 6, 8 and dashed curv es 7, 9 are for "A" and A states, respectively thick curves 1, 6, 7 are from this work (after preliminary optimisation through the coefficients A21, A22, Cg, Oqh and Oc oh ) and thin curves 2, 8, 9 are from [25] the dotted curve 3 is our recalculation (without contributions of S-O and exchange interactions) using parameters from [17] and [23] curve 4 is the analytic representation DMBEfV from [26] curve 5 is from the ab initio data of [27],...

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