The B-Z transition of a polynucleotide with a 10-base pair repeating sequence

In this communication we report the synthesis and characterization of a defined-sequence, alternating purine-pyrimidine polymer with a 10-base pair repeating unit: poly[d(CGCGCGTGCA)]. It is seen that the polymer can undergo a right-left-hand helical transition, but the conformational transition requires much higher salt concentration than with poly[d(G-C)]. The results are interpreted in terms of interaction of the polymer with solvent molecules.