| Popis: |
The solution structures of the oligomeric DNAs d(GGGGCCCC) 2 (I), d(CGCGCGCG) 2 (II), d(GGGTACCC) 2 (III), d(GGGATCCC) 2 (IV), d(CGCTAGCG) 2 (V), d(GGAATTCC) 2 (VI), d(GGATCC) 2 (VII) and d(GCATGC) 2 (VIII) were analyzed. In low-salt solutions the overall conformation of these oligomers is predominantly B-like but not A-like as observed in crystals of (I), (III) and (IV) by others. The conformation of (I), (III) and (IV) containing homo (dG) · (dC) tracts is different from that of mixed-sequence DNAs like in (II) and (V) or in poly(dG-dC) · poly (dG-dC). Also (IV), (VI), (VII) and (VIII) involving restriction enzyme recognition sites reveal spectral differences. Attempts to correlate these spectral differences with structural differences within the B-family on the basis of calculated fine structures were started. |
