Rate of Conformational Transitions

The divergence between the rate of conformational transitions and the decay of the torsional autocorrelation functions (and hence local relaxations)... 

Rate of Conformational Transitions in Biological Macromolecules and Their Analog... 

Single-molecule studies have revealed that some branched RNA species exhibit surprisingly heterogeneous dynamics (Lemay et ah, 2006 Tan et ah, 2003 Zhuang et al, 2002), while others (such as a simple 4H RNA junction) do not. Rates of conformational transitions can vary a hundred... 

Use of the Interaction of Ultraviolet L ht With Chain Molecules to Study the Rate of Conformational Transition... 

D. Tabak and H. Morawetz, Rates of conformational transitions in solutions of randomly coiled polymers. III. Cis-trans isomerization of azobenzene residues in the backbone of polyamides, Macromolecules 3, 403 410 (1970). 

Umbrella sampling for ensembles of trajectories can be carried out in close analogy to the procedure described above. For the purpose of computing rate constants (in this case the rate of conformational transitions), we focus on computing the reversible work to confine trajectories endpoints to state B, given that these trajectories begin in state A. P (A, t) is defined to be the distribution of A at the endpoints of trajectories initiated in A,... 

SOME STUDIES ON THE RATES OF CONFORMATIONAL TRANSITIONS AND OF CIS-TRANS ISOMERIZATIONS IN FLEXIBLE POLYMER CHAINS... 

The use of UV spectroscopy has two important advantages compared to the NMR method for the study of rates of conformational transitions ... 

STUDIES OF RATES OF CONFORMATIONAL TRANSITIONS BY EXCIMER FLUORESCENCE... 

Rates of conformational transitions and cis-trans isomeri-zations in polymers, a new look at rubber elasticity theory and new synthetic procedures for stiffening polymer chains are some of the new scientific developments. The book concludes with two approaches for the use of polymers in the important field of slow drug release. The authors are all well-known scientists and include Nobel Laureate Paul Flory, first recipient of the Polymer Division Award which was presented at this Symposium. 

My research activities have been largely concentrated in studies of 1. solid state polymerization, 2, kinetics of reactions in systems containing polymers, and 3. rates of conformational transitions and isomerizations in flexible polymer chain molecTiles. 

Intramolecular excimer fluorescence involves a conformational transition furing the lifetime of an excited chromophore and it can, therefore, used to study conformational transitions on the timescale of 10 ° sec. We have used this technique to study the behavior of copolymers and to define the dependence of the rate of conformational transitions on the viscosity of the medium. 

The rates of conformational transitions of a chain encompass an enormously wide range. Local rearrangements including only a few adjacent monomers are usually rapid and take place with rates similar to those in ordinary liquids. Conformational changes of more extended sequences require much longer times. In particular, relaxatory modes associated with the chain... 

As a conclusion, it can be stated that the use of adequate model peptides allows one to obtain information on the molecular dynamics of the peptide chain by means of fluorescence techniques. Both conformational and configurational effects have to be taken into account when analyzing the photophysics of these aromatic peptides. Moreover, rate constants and thermodynamic parameters of conformational transitions can be obtained. Until now, no other technique offers the possibility to obtain quantitative information on the molecular dynamics of peptides and, to our knowledge, no other reports on the rate of conformational transitions of peptides can be found in literature. 

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