Adhesion-induced DNA naturation.
DNA adsorption and naturation is modeled via two interacting flexible homopolymers coupled to a solid surface. DNA denatures if the entropy gain for unbinding the two strands overcomes the loss of binding energy. When adsorbed to a surface, the entropy gain is smaller than in the bulk, leading to a stronger binding and, upon neglecting self-avoidance, absence of a denatured phase. Now consider conditions where the binding potentials are too weak for naturation, and the surface potential too weak to adsorb single strands. In a variational approach it is shown that their combined action may lead to a naturated adsorbed phase. Conditions for the absence of naturation and adsorption are derived too. The phase diagram is constructed qualitatively.
Allahverdyan
A E
AE
Yerevan Physics Institute, Alikhanian Brothers Street 2, Yerevan 375036, Armenia.
Gevorkian
Zh S
ZhS
Hu
Chin-Kun
CK
Nieuwenhuizen
Th M
TM
D004247:DNA / Q000737:chemistry*; D008956:Models, Chemical; D009691:Nucleic Acid Denaturation; D000267:Tissue Adhesions
D004247:DNA