Frustrations in polymer conformation in gels and their minimization through molecular imprinting.

We report an experimental realization of a gel system in which frustrations exist and can be minimized, thus meeting two crucial criteria predicted to enable memory of conformations in polymers. The gels consist of a thermosensitive major monomer component and two minor components. One minor component is positively charged and will form complexes around negatively charged target molecules placed in solution.

Pathways for protein folding: is a new view needed?

Theoretical studies using simplified models of proteins have shed light on the general heteropolymeric aspects of the folding problem. Recent work has emphasized the statistical aspects of folding pathways. In particular, progress has been made in characterizing the ensemble of transition state conformations and elucidating the role of intermediates.

On the theory of folding kinetics for short proteins.

Background: Recent data have suggested two principles that are central to the work we describe here. First, proteins are the result of evolutionary 'sequence selection' to optimize the energy of the native state. Second, the overlap with the native state is a qualitatively suitable reaction coordinate for modeling folding kinetics.

Fractality of DNA texts.

By performing several statistical tests, we confirm that long-range correlations exist and are typical for long eukaryotic DNA sequences. Different types of "critical exponents" for characterization of DNA fractality are discussed. As to possible explanation of the phenomenon, our computer simulations indicate that simple mosaic structure of genome, without correlations between blocks, cannot be solely accounted for the observed statistical properties of DNA texts.

Dynamics of double stranded DNA reptation from bacteriophage.

The dynamics of dsDNA release process from a phage head has been analyzed theoretically. The process was considered as dsDNA reptation through the phage tail. The driving force is assumed to be the decrease of the DNA globule free energy on its releasing from the head in the surrounding medium.

On the compact form of linear duplex DNA: globular states of the uniform elastic (persistent) macromolecule.

A theory of collapse of DNA considered as unifilar homopolymer is suggested. The collapse is interpreted as the coil-globule transition. Three reasons of the collapse such as the confinement in a microcavity, the influence of poor low-molecular-weight solvent and the influence of polymeric solvent were studied.

On the toroidal condensed state of closed circular DNA.

The influence of double helix torsional elasticity on the compaction and structure of circular DNA compact form is studied theoretically in the case when the compact (globular) form has torus shape. For closed circular DNA the topological invariant, the linking number, yields a strict connection between conformation of the double helix considered as unifilar homopolymer and elastic energy of torsional twisting. The contribution of torsional elasticity to the free energy of the toruslike globule is calculated.