Jong Goo Kim

Learn More
Proteins serve as molecular machines in performing their biological functions, but the detailed structural transitions are difficult to observe in their native aqueous environments in real time. For example, despite extensive studies, the solution-phase structures of the intermediates along the allosteric pathways for the transitions between the relaxed (R)(More)
Anisotropic X-ray scattering patterns of transiently aligned protein molecules in solution are measured by using pump-probe X-ray solution scattering. When a linearly polarized laser pulse interacts with an ensemble of molecules, the population of excited molecules is created with their transition dipoles preferentially aligned along the laser polarization(More)
Conformational substates of proteins are generally considered to play important roles in regulating protein functions, but an understanding of how they influence the structural dynamics and functions of the proteins has been elusive. Here, we investigate the structural dynamics of sperm whale myoglobin associated with the conformational substates using(More)
Two series of epitaxial CoPt and FePt films, with nominal thicknesses of 42 or 50 nm, were prepared by sputtering onto single crystal MgO(001) substrates in order to investigate the chemical ordering and the resultant magnetic properties as a function of alloy composition. In the first series, the film composition was kept constant, while the substrate(More)
Relative free energies of h1 1 1i tilt boundaries in 1.7-lm-thick Al films were compared with boundary enthalpies obtained via molecular dynamics simulations. Grain growth studies in 25 and 100-nm-thick Al films were compared with simulations. The sources of the differences between experimental and simulational results are discussed.
Relative grain boundary energy as a function of misorientation angle was measured in a cube-oriented, 120 µm-thick Al foil and in a <111> fiber-textured, 1.7 µm-thick Al film using a multiscale analysis of the grain boundary dihedral angles. For the Al foil, the energies of low-angle boundaries increased with misorientation angle, in good agreement with the(More)
Generally, a protein molecule should form its native structure to perform its biological function in the living cell. However, the failure of proper folding, i.e. misfolding, occurs occasionally and this causes aggregation and/or degradation of the protein, which is potentially linked to protein mis-folding diseases, e.g. prion disease and Parkinson's(More)
Homodimeric hemoglobin (HbI) consisting of two subunits is a good model system for investigating the allosteric structural transition as it exhibits cooperativity in ligand binding. In this work, as an effort to extend our previous study on wild-type and F97Y mutant HbI, we investigate structural dynamics of a mutant HbI in solution to examine the role of(More)
The [Au(CN)2 (-)]3 trimer in water experiences a strong van der Waals interaction between the d(10) gold atoms due to large relativistic effect and can serve as an excellent model system to study the bond formation process in real time. The trimer in the ground state (S0) exists as a bent structure without the covalent bond between the gold atoms, and upon(More)