Structure-function studies, of proteins

Prasanna RR, Vijayalakshmi MA. Immobilized metal-ion affinity systems for recovery and structure-function studies of proteins at molecular, supramolecular, and cellular levels. Pure Appl Chem 2010 82 39-55. 

Structure-function studies of IFN-y carried out using the synthetic peptide approach and site-specific antibodies indicated that both the N- and C-terminal regions of the protein were not only functionally important, but also accessible at the surface of the molecule. The x-ray crystal structure of human IFN-y has been determined and reveals that in the IFN-y homodimer both the N- and the... 

Recently, active recombinant a-LTX has been generated using bacteria in which both thioredoxin reductase and glutathione reductase are inactivated to improve the formation of disulphide bonds in expressed proteins (Li et al. 2005). The toxin is expressed as a fusion with glutathione-S-transferase (GST), which is used for affinity purification of the recombinant toxin and can be subsequently removed by selective proteolysis. Considering the relative ease of generating recombinant proteins in bacteria, this approach will facilitate structure-function studies of a-LTX. 

Toraya, T., 1998, Recent structure-function studies of B12 coenzymes in diol dehydrase. In Vitamin B12 and B12-proteins(B. Krautler, D. Arigoni, and B. T. Golding, eds.), Wiley-VCH, Weinheim, pp. 303n320. 

Isolation of the immunophilin cDNAs has rendered possible the production and the structure-function study of these proteins by site-directed mutagenesis. In addition, yeast strains have been constructed where the endogenous ligands for CsA and FK506 have been replaced with their human counterparts. Such strains provide convenient assay systems for the stracture-activity studies of putative immunosuppressants (Koltin et al, 1991). The advances in immunosuppression are yet another salient example of the contributions of molecular biology to drug design and development. 

The reconstitution process is a well practiced methodology to examine the structure-function relationship of proteins. The reconstitution method. Fig. 3-1, (exemplified for myoglobin) involves the exclusion of the native active center from the protein, e.g. an ion or a cofactor, to yield the respective apo-protein (or hollow-protein). The implanting (or reconstitution) of a structurally-related cofactor or ion generates the semisynthetic reconstituted protein that might exhibit new tailored functions that are not present in the native protein. The reconstitution process has been extensively practiced upon studying mechanistic aspects of photoinduced ET... 

Nuclear Magnetic Resonance (NMR) is one of only a few scientific techniques that have been widely applied in many different areas such as physics, chemistry, biology and medicine. Today, NMR plays a crucial role in structure-function studies of organic and inorganic compounds and of large biomolecules, particularly proteins and DNA. In medicine it is one of the most important imaging techniques available to physicians and it also has extensive applications in pharmaceutical research. In this special issue of NMR of Proteins and Small Biomolecules, review chapters cover a wide-range of topics on some of the latest developments in NMR techniques and their applications. 

Such mass spectrometric determinations of reactive sites in intact protein strac-tures by chemical modifications in proteins have been found highly useful in strac-ture—function studies of proteins [15], such as for ion-chatmel proteins (porins see Fig. 10.11). The structures of several bacterial porins have been determined by X-ray crystallography, such as the porin from Rhodobacter capsulatus (R. c.-porin) [132] which forms a trimeric complex of 16 18-stranded P-barrels. A characteristic stmc-ture element of R. c.-porin is a central constriction loop inside the P-barrel, which has been suggested as the central site determining cation/anion permeability and... 

Toraya, T. Recent Structure-Function Studies of B,2 Coenzymes in Diol Dehydrase. In Vitamin B12 and Bj2-Proteins Krautler, B.. Arigoni. D.. Golding. B.T., Eds. Wiley-VCH. Verlag GmbH Weinheim. 1998 303-320. 

E.Y. Chekmenev, P.L. Gor kov, P.L. Cross, A.M. Alaouie, A.I. Smirnov, Flowthrough lipid nanotube arrays for structure-function studies of membrane proteins by solid-state NMR spectroscopy, Biophys. J. 91 (2006) 3076. 

Circular-dichroism studies indicate that native bovine CRALBP and human rCRALBP have similar secondary structures, ligand binding, and thermal-stability properties, and support the validity of pursuing structure-function studies of the recombinant protein (29). 

USE OF ENZYME KINETIC DATA IN THE STUDY OF STRUCTURE-FUNCTION RELATIONSHIPS OF PROTEINS... 

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