Conformational change associated with

Westwood, J.T. Wu, C. (1993). Activation of Drosophila heat shock factor Conformational change associated with monomer to trimer transition. Mol. Cell. Biol. 13, 3481-3486. 

Evidence for conformational changes associated with the binding of ligands has also been provided by Rao et al. (61) who found that AMP markedly reduced the reactivity of SH groups, suggesting that the presence of the allosteric inhibitor changes the conformational state of the enzyme. 

The situation for Fe11 porphyrin is rather similar, with the existence of 5 = 0, 1 and 2 states. The iron in Fe(TPP)(THF)2 lies in the plane of the porphyrin.647 This result is of considerable relevance to model systems for hemoglobin and the question of the trigger for the conformational change associated with the cooperative uptake of dioxygen. In this example the presence of a symmetrical weak axial field is the crucial factor. While this particular situation probably does not occur in any natural hemoprotein, these results demonstrate conclusively that high-spin Fe11 will fit into the porphyrin plane. 

Heat and work can be distinguished in terms of random molecular motion versus directed or coordinated motion. In muscle cells, from organisms as simple as yeast to those as complex as humans, the hydrolysis of ATP provides the driving force for the interactions and conformation of two cellular proteins, myosin and actin. Conformational changes associated with the binding and release of ATP and ADP provide the means by which a coordinated movement of these muscle cells is possible to do mechanical work. 

Ridge, K. D., Abdulaev, N. G., Zhang, C., Ngo, T., Brabazon, D. M., and Marino, J. P. (2006). Conformational changes associated with receptor-stimulated guanine nucleotide exchange in a heterotrimeric G-protein alpha-subunit—NMR analysis of GTP gamma S-bound states. / Biol. Chem. 281, 7635-7648. 

Regulatory processes such as muscle contraction are controlled by temporary conformational changes associated with metal ion co-ordination. Such regulatory processes are frequently associated with metal ions such as Mg2+, Ca2+ and Mn2+ (which possesses a d5 configuration with no crystal field preference for any particular co-ordination geometry). Muscle contraction is controlled by the binding of calcium ions to the protein troponin (Fig. 10-4), with a feed-back loop controlling the release and uptake of calcium ions from an ATP-ase, an enzyme which catalyses the hydrolysis of ATR... 

Structural Characterization of Conformational Changes Associated with Ion Translocation 41 Change in Exposure to Modifying Agents 41... 

STRUCTURAL CHARACTERIZATION OF CONFORMATIONAL CHANGES ASSOCIATED WITH ION TRANSLOCATION... 

The potential to study conformational changes associated with a variety of biological phenomena on a time-resolved basis has served as an important driving force for the development of new instrumental approaches for the measurement of CD. Two recently developed experimental techniques have demonstrated that the capability to obtain CD information on the nanosecond to picosecond time scale is possible. 

Goh, C.S., Milbum, D. and Gerstein, M. (2004) Conformational changes associated with protein-protein interactions. Curr. Opin. Struct. Biol. 14, 104-109. 

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