Ligand affinities

Shuker S B, P J Hadjuk, R P Meadows and R P Fesik 1996. Discovering High-affinity Ligands fc Proteins SAR by NMR. Science 274 1531-1534. 

The two states have the same affinity for ATP but differ with respect to their affinity for the substrate F6P, the allosteric effector ADP and the inhibitor PEP. Because of these differences in affinity, ligand binding can shift the equilibrium between the R and T states to favor one or the other state depending on which ligand is bound. 

Gene Product Origin Molecular Mass (kD) Secreted Affinity Ligand... 

A very similar cloning strategy has been used for the 48-kDa subunit of the glycine-receptor channel by Betz and collaborators [4]. Strychnine was used as an affinity ligand, and synthetic oligopeptides were constructed from the purified material. They have been used to screen cDNA libraries. 

For reasons that are not yet clear, skeletal muscle transverse (T)-tubule membranes contain 50-100-fold more high affinity DHP receptors than any other source yet identified [43,45]. Transverse tubule membranes contain 30-70 pmol/mg protein of DHP receptors that bind [ H]PN 200-100 with a of 0.1-0.2nM. The strategy utilized for the purification of L-type channels was similar to that used for the purification of other high affinity ligand binding proteins, and its success was predicted from the prior use of such an approach for the purification of other ion channels [54,55]. Thus the L-type channels were purified as high affinity DHP receptors, with the anticipation that the purified component(s) would constitute functional Ca channels. 

Immunosorbents have also found applicability in on-line SPE analysis. An antibody is immobilized on to a silica support and used as an affinity ligand to retain targeted analytes. Components not recognized by the antibody are not retained and some degree of selectivity is attained. Recoveries of 87-103% were obtained for atrazine, simazine, DEA, propazine, and terbuthylazine at the 0.2 xgL concentration level when using immunosorbent SPE (80 mg silica and 2 mg anti-atrazine and anti-chlortoluron antibodies) on-line with LC/APcI-MS however, this method is not applicable to DIA (0% recovery). This compound may be better retained when using an... 

Fundamentally, FBDD is a general approach aimed at deriving high affinity ligands for macromolecular targets starting from low MW binders, which are usually identified by the use of the aforementioned biophysical techniques [1, 2, 7, 8]. 

Shuker SB, Hajduk PJ, Meadows RP, Fesik SW. Discovering high-affinity ligands for proteins - SAR by NMR. Science 1996 274 1531-1534. 

Yamada K, Rice KC, Flippen-Anderson JL, Eissenstat MA, Ward SJ, Johnson MR, Howlett AC. (Ami noalky Ijindole iso thiocyanates as potential electrophylic affinity ligands for the brain cannabinoid receptor. J Med Chem 1996 39 1967-1974. 

Immobilization of Proteins (Enzymes) and Affinity Ligands Mediated by CDI... 

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