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Toward an Unified Description for Thermodynamics,
    Folding Kinetics, and Mutagenesis of Proteins”

* Speaker : Prof. Ik Soo Chang[Pusan National University]
* Place : Physics Seminar Room (Science Bldg, 3-201)
* Date & Time : Oct,합법 토토 사이트16Fri)합법 토토 사이트4:00 ~ 5:00 pm
 
Abstract
A multiscale-heterogeneous protein energy function was developed for the biophysical study of the
thermodynamics, folding kinetics, and mutagenesis of proteins. After hybridizing an합법 토토 사이트atomic합법 토토 사이트force-
field into a coarse-grained energy function to account for the specificity of a합법 토토 사이트sequence합법 토토 사이트of합법 토토 사이트amino
acids even with the high structural homology, we constructed an exact free energy landscape of a
given protein and characterized its thermodynamics and folding-unfolding kinetics via합법 토토 사이트a합법 토토 사이트Chevron
plot based on solving exactly a master equation, which would enable us to pursue합법 토토 사이트a합법 토토 사이트mutagenesis
application. Our approach was applied successfully for resolving a controversy합법 토토 사이트about합법 토토 사이트the합법 토토 사이트folding
mechanism of fast folding proteins.  

Recent experiments claiming that BBL protein follows a global downhill folding raised an important
controversy as to the folding mechanism of fast folding proteins. Under the global downhill folding
scenario not only proteins undergo a gradual folding, but also folding events along the continuous
folding pathway could be mapped out from the equilibrium denaturation experiment. Based on the
exact calculation using a free energy landscape, relaxation eigenmodes from합법 토토 사이트a합법 토토 사이트master합법 토토 사이트equation,
and Monte Carlo simulation of an합법 토토 사이트extended합법 토토 사이트Munoz-Eaton합법 토토 사이트model합법 토토 사이트that합법 토토 사이트incorporates합법 토토 사이트multiscale-
heterogeneous pairwise-interactions between amino acids, here we show that the very nature of a
two-state cooperative transition such as a bimodal distribution from an exact free energy landscape
and biphasic relaxation kinetics do manifest in the thermodynamics합법 토토 사이트and합법 토토 사이트folding-unfolding합법 토토 사이트kinetics
of BBL and peripheral subunit-binding domain (PSBD) homologue. Our results provide an unequivocal
resolution to the fundamental controversy related to합법 토토 사이트the합법 토토 사이트global합법 토토 사이트downhill합법 토토 사이트folding합법 토토 사이트scheme,합법 토토 사이트whose
applicability to other proteins should be critically re-examined.

Contact Person : Prof. Ki Bong Lee (054-279-2068, kibong@postech.ac.kr)

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