Conformational change of proteins

It is important to characterize the material adsorbed at the interface, as well as the conformation of the adsorbed proteins, because it determines the properties of the emulsions and gels. However, little is known about the conformational changes of proteins upon adsorption at oil-water interfaces. The main reason for this is the lack of experi-... 

Tama, F. Sanejouand, Y.H., Conformational change of proteins arising from normal mode calculations, Protein Eng. 2001,14, 1-6... 

Calleja, V., Ameer-Beg, S. M., Yojnovic, B., Woscholski, R., Downward, J. and Larijani, B. (2003). Monitoring conformational changes of proteins in cells by fluorescence lifetime imaging microscopy. Biochem. J. 372, 33 40. 

Lumry, R. and H. Eyring. 1954. Conformation changes of proteins. J Phys Chem 58 110-120. 

Prediction of the conformational change of the protein under binding is a challenge. New structural parameters based on high resolution X-Ray structures have been presented recently (69). Such studies open the door to a more extended analysis of conformational changes of protein cavity when binding with different ligands. 

Absorbance of peptide bonds at 2170 nm is usually used as a key band for the calibration of protein content measurement. However, the intensity of the absorption depends on the structure and conformation of the protein. Yamashita et al [8] investigated the change in absorption at 2170 nm caused by the conformational change of protein using bovine serum albumin (BSA) as the model protein. A mixture of dithiothreitol (a reducing agent) and BSA (5%) was taken in a quartz cell attached to the NIR instrument, and then spectra were recorded at 10-minute intervals. Dithiothreitol reduced the disulfide bond in BSA. The... 

Evidence indicates that microwaves affect the kinetics of conformation changes of proteins such as P-lactoglobulin (Bohr and Bohr, 2000). It is thought that even approximately a few GHz can excite protein molecules. Consequently, the kinetics of conformational changes of the protein molecule are enhanced, and this denaturing effect is... 

Alfimova, E.Ya., and Likhtenshtein, G.I. (1979) Investigation of structure and conformational change of proteins by the inductive resonance energy transfer, Advans. Mol. Relax. Interact. Proc. 14, 47-89. 

Likhtenshtein, G.I., and Bobodzhanov, P. Kh. (1968) Investigation of die structure and local conformational changes of proteins and enzymes using double paramagnetic labels. Biofizika, 13, 757-764. 

Lo YL and Rahman YE. Effects of Lipids on the Thermal stability and Conformational Changes of Proteins Ribonuclease A and Cytochrome C. Int JPharm 1998 161 137-148. 

The results show an increased enantioselectivity under MW activation. The origin of such an effect could be manifold a most efficient removal of light alcohols or water [156], an entropic effect due to dipolar polarization able to induce a previous organization of the system, and conformational changes of proteins not only related to temperature [157]. 

Absorption of a photon by the chromophore induces primary photoreaction, followed by conformational changes of protein, and eventually activates transducin. This is called the bleaching process because rhodopsin loses its color. To investigate the primary photoreaction processes in rhodopsin, two spectroscopic approaches have been applied low-temperature and time-resolved spectroscopies... 

Information about the secondary structures (a-helices, /5-sheets, random coil) can be useful for understanding conformation changes of proteins upon the immobilization process. More specifically, circular dichroism (CD) [70] and FT-IR spectroscopy [56, 58, 61, 71-73] have been applied to study the structural characteristics of various proteins adsorbed on mineral surfaces. Kondo and coworkers [70] have studied the modification in a-helix content of proteins adsorbed on ultrafine silica particles with CD and found a decrease upon immobilization. Circular dichroism is not usually used because this technique is applicable only for the study of enzymes immobilized on nano-sized mineral particles due to problems arising from light scattering effects. On the other hand, infrared spectroscopy does not suffer from light scattering perturbations and has thus been used for the study of the conformation of proteins when they are immobilized on solid supports [57, 58]. 

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