Increase in temperature induces the Z to B transition of poly[d(G‐C)] in water‐ethanol solution

[摘要]

An increase in temperature from 20 to 50° C results in the complete transition from the Z to B form of poly(d(G-C)], dissolved in a 55% ethanol-water solution. The transition is fully reversible and displays a slow kinetics. The transition profiles for the free polynucleotide and for that in the presence of ethidium bromide, which is known to stabilize the B form, are obtained by circular dichroism. Based on these data the enthalpy value for the B-Z transition in our conditions is estimated to be ΔH _BZ = −0.7 .

[学科分类] 生物化学/生物物理

[关键词] Poly[d(G-C)];Ethidium bomide;Z form;Circular dichroism;B-Z trantion enthalpy