Biochemical affinity

Chromatography is the most versatile chemical separation method we have available at present. In it, a mixture is separated into various components on the basis of differences in the speed at which these components move through a chromatographic column. What differentiates their speeds is that the column slows them down by one mechanism or another. Many different retarding effects can be exploited, based on such diverse molecular properties as solubility, charge, size, adsorption, or biochemical affinity. Here we will consider partition chromatography, which is based on differences in (solvation) energy. 

An array surface that provides selective chemical and biochemical affinity for retention of proteins, peptides, and various bio-molecules without traditional chromatographic purification procedures. 

Physical and biochemical affinity of the sorbent/carrier and the material being dried... 

Liquid chromatography is rather more widely applicable than gas-liquid chromatography and in some forms has the capability to handle larger amounts of substance. All the main forms of LC are used, namely adsorption, partition, ion exchange, and gel filtration, and some newer forms of chromatography including metal-chelate adsorption, hydrophobic adsorption, and, particularly for biochemicals, affinity chromatography. 

Affinity chromatography A method of separating and purifying compounds using their biochemical affinity to the stationary phase. 

Polyelectrolytes based on ethyleneimine are also used to treat drinking water and process water, and as agents for preventing lime deposits (407) in water extraction. The binding power of PEI is utilized for the treatment of effluents (408). Biochemical reactions can be catalyzed by using the complex-forming properties of PEIs and their affinity for organic substrates (409). 

ADP-Ribosyl transferase (from human placenta) [9026-30-6]. Purified by making an affinity absorbent for ADP-ribosyltransferase by coupling 3-aminobenzamide to Sepharose 4B. [Burtscher et al. Anal Biochem 152 285 1986.]... 

Angiotensin (from rat brain) [70937-97-2 M 1524.8. Purified using extraction, affinity chromatography and HPLC [Hermann et al. Anal Biochem 159 295 1986],... 

Avidin (from egg white) [1405-69-2] Mr -70,000. Purified by chromatography of an ammonium acetate soln on CM-cellulose [Green Biochem J 101 774 1966]. Also purified by affinity chromatography on 2-iminobiotin-6-aminohexyl-Sepharose 4B [Orr 7 Bio/C/iew 256 761 1981]. It is a biotin binding protein. 

Cathepsin B (from human liver) [9047-22-7] Mr 27,500 [EC 3.4.22.1]. Purified by affinity chromatography on the semicarbazone of Gly-Phe-glycinal-linked to Sepharose 4B, with elution by 2,2 -dipyridyl disulfide [Rich el al. Biochem J 235 731 1986 Methods Enzymol 80 551 1981]. 

EC 1.15.1.1]. Purified by DEAE-Sepharose and copper chelate affinity chromatography. The preparation was homogeneous by SDS-PAGE, analytical gel filtration chromatography and by isoelectric focusing [Weselake et al. Anal Biochem 155 193 1986 Fridovich J Biol Chem 244 6049 7969]. 

EC 1.1.1.27]. 40-Fold purification by affinity chromatography using Sepharose 4B coupled to 8-(6-aminohexyl)amino-5 -AMP or -NAD. [Lees et al. Arch Biochem Biophys 163 561 7974 Pesce et al. J Biol Chem 239 1753 7964.]... 

Purified by dissolving in Triton X-100 and deoxycholate, and by affinity chromatography on concanavalin A-Sepharose and AMP-Sepharose [Grondal and Zimmerman Biochem J 245 805 1987]. 

Protease nexin (From cultured human fibroblasts) [148263-58-5], Purified by affinity binding of protease nexin to dextran sulfate-Sepharose. [Farrell et al. Biochem J 237 707 1986.]... 

Rcnsl dipcptidflsc (from porcine kidney cortex) [9031-96-3] Mr 47,000 [EC 3.4.13.11]. Purified by homogenising the tissue, extracting with Triton X-100, elimination of insoluble material, and ion-exchange, size exclusion and affinity chromatography. [Hitchcock et al. Anal Biochem 163 219 7957.]... 

Subtilisin (from Bacillus subtilis) [9014-01-1 ] [EC 3.4.21.62]. Purified by affinity chromatography using 4-(4-aminophenylazo)phenylarsonic acid complex to activated CH-Sepharose 4B. [Chandraskaren and Dhai Anal Biochem 150 141 7955]. 

Purified by a [anti-human amniotic fluid-TIMP]-Sepharose immuno-affinity column eluted with 50mM glycine/HCl pH 3.0 buffer that is 0.5M in NaCl then by gel film [Cawston et al. Biochem J 238 677 1986]. 

Saturation binding, a biochemical procedure that quantifies the amount of traceable ligand (i.e., radioligand) to a receptor protein. It yields the affinity of the ligand and the maximal number of binding sites (i)max) see Chapter 4.2.1. 

Kendall, J. M., et al. (1992). Engineering the Ca2+-activated photoprotein aequorin with reduced affinity for calcium. Biochem. Biophys. Res. Commun. 187 1091-1097. 

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