Concanavalin characterization

Tunicamycin specifically inhibits cell division and pairing between the mating types of Tetrahymena pyriformis. The glycoproteins involved in this mating process have not yet been characterized, but may coincide with new, concanavalin A receptor-sites that appear during conjugation.495... 

Western blotting has become an important, modern technique for analysis and characterization of proteins. The procedure consists of, first, the electrophoretic transfer (blotting) of proteins from polyacrylamide gels to synthetic membranes. The transferred blots are then probed using immunological detection methods to identify proteins of specific structure and/or function. In this experiment, bovine serum will be fractionated by SDS-PAGE and the proteins blotted onto a nitrocellulose membrane. Serum glycoproteins will be identified by their specific interaction with the lectin concanavalin A. 

Stirpe, F., Olsnes, S., and Pihl, A. (1980) Gelonin, a new inhibitor of protein synthesis, nontoxic to intact cells. Isolation, characterization, and preparation of cytotoxic complexes with concanavalin A. J. Biol. Chem. 255, 6947—6953. 

The lectins are saccharide-binding proteins that cause cell agglutination. The best characterized of the lectins is concanavalin A (Con A). Con A is devoid of carbohydrate binding activity in the absence of added metal. Each monomeric unit of Con A has two binding sites, named SI (the transition metal site) and S2 (the calcium site). The SI site binds a variety of divalent transition metals, including Mn, Ni, Co, Cd, Zn, Fe, and Cu, although Mn is probably the metal used in vivo. The S2 site is not formed until SI is occupied. Both SI and S2 must be occupied before saccharide will bind. 

Obaidat, A.A. Park, K. Characterization of glucose dependent gel-sol phase transition of the polymeric glucose-concanavalin A hydrogel system. Pharm. Res. 1996, 13, 989-995. 

Rocklin, R.E. (1975) Partial characterization of leukocyte inhibitory factor by concanavalin A-stimulated human lymphocytes (LIF Con A). J. Immunol. 114 1161-1165. 

The absorption and circular dichroism spectra of the blue colour produced by tri-iodide ions in amylose have been characterized. Four fundamental Raman lines were observed for bound to amyloses which were not dependent on the DP in the range 20-100 or the excitation wavelength. Concanavalin A does not react with amylose but does react with the amylose-iodine complex although the complex can be dispersed by shaking. The complex is non-specific as it cannot be displaced by concanavalin A-specific sugars. 

The best known plant L. are Concanavalin A (Con A) from jack beans (Canavalia ensifornus), which was crystallized in 1919 by Sumner, and the agglutinins from wheat germ (WGA), lima beans, green beans (Phaseolus), castor beans Ricinus) and potatoes. WGA is very well characterized, and L. with similar specificities and structure are present in rye and barley. Seeds from 90 other members of the Triticeae tribe of... 

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