Polysaccharides with concanavalin

Goldstein L, Hollerman C, Smith EE. Protein-carbohydrate interaction. II. Inhibition studies on interaction of concanavalin A with polysaccharides. Biochemistry 1965, 4, 876-883. 

The influence of metal ions on the saccharide binding activity and on the conformation of lectins is widely reported. Ethylenedinitrilotetra-acetic acid has been shown to remove Ca + and Mn + ions from concanavalin A at pH 5.3 with a concomitant loss of saccharide-binding activity, which could be partly recovered by addition of either Ca + or Mn + or fully recovered by addition of both ions together. Concanavalin A when complexed with polysaccharide prior to treatment with ethylenedinitrilotetra-acetic acid is largely resistant to the action of this agent, which suggests that the afiSnity of concanavalin A for Ca and Mn + increases on binding of carbohydrate. 

Concanavalin A is an antibody-like protein isolated from the jack bean. 82 It was shown to form a precipitate with glycogen and with yeast mannan, and was later also used to differentiate between glycogen-like polysaccharides from various sources.283 284 It has now been shown that concanavalin A forms a precipitate only with branched polysaccharides which contain terminal, nonreducing a-D-glucopyranosyl or a-D-manno-pyranosyl groups.18 The combining sites of the protein appear to be directed against the 2-deoxy-a-D-aratano-hexopyranosyl system.2 ... 

The selective precipitation of some polysaccharides with antisera, which has been studied by Heidelberger and coworkers, is an important analytical tool, but the purification of preparative amounts of material by this method seems to be impractical. This could also be said of precipitation with the globulin from Jack-bean meal, concanavalin A, which has been used by Smith and his coworkers for fractionation. ... 

Insoluble concanavalin A has already been used in the purification of glycoproteins,and, in view of its commercial availability, it will no doubt prove useful in structural, studies. Furthermore, the in-solubilized lectin may be used in column form for the separation of monosaccharide mixtures and of polysaccharide mixtures " it has been demonstrated that mixtures of carbohydrates not separable by complex-formation with concanavalin A in solution may be separated by using the immobilized form,... 

The exocellular polysaccharides released by yeast during fermentation and aging on the lees may be isolated by precipitation with ethanol, or membrane ultrafiltration at a cutoff of 10 000. They may be fractionated by two processes precipitation with hexadecyltrimethylammonium bromide (Cetavlon) and affinity chromatography on a Concanavaline A-Sepharose gel column. The composition of the fractions obtained by these two methods is very similar, consisting of the following ... 

Poly-amido-saccharides (PAS) (Figure 2.9) are synthetic carbohydrates that can mimic natural polysaccharides as they can bind lectin concanavalin A (ConA) at the same site as natural carbohydrates. PAS are synthesised via anionic ROP of a P-lactam sugar monomer. In PAS, the pyranose rings are linked through the 1- and 2-positions by an amide with a-stereochemistry. P-lactam sugar is synthesised from benzyl-protected D-glucal [56]. 

Carbohydrate—protein complex-formation. Some factors affecting the interaction of D-glucose and polysaccharides with concanavalin A. Carbohydr. Res. , 89-100. 

A polysaccharide (mol. wt. 9.5 x 10 ) containing residues of D-galactose, D-mannose, and L-fucose (12 3 4) has been purified from the fruiting bodies of Flammulina velutipes. The structure (23) is based on the results of methyla-tion analysis, i.r. spectroscopy, and interaction studies with concanavalin A. Every third (1 -> 6)-linked a-D-galactopyranosyl residue is substituted with either an L-fucopyranosyl group or a 3-0-a-D-mannopyranosyl-L-fucopyranosyl unit. 

The chemistry and immunostimulant properties of the cell walls of mycobacteria and related organisms have been reviewed. Concanavalin A has been shown to react with three antigenic polysaccharides present in culture filtrates of Mycobacterium tuberculosis, these polysaccharides were isolated by direct precipitation and affinity chromatography. A mannan esterified with succinic acid has been isolated from extracts of mesosomal and plasma membranes of Micrococcus lysodeikticus The polysaccharide was precipitated by concanavalin A, but it was attacked only slightly by jack-bean a-mannosidase. I.r. spectroscopy indicated the presence of both esterified and free carboxy-groups in the mannan. Mesosomal membranes isolated from M. lysodeikticus, unlike preparations of plasma membranes, were unable to catalyse the incorporation of D-[ C]mannose from GDP-D-[ C]mannose into the mannan it appears that the membrane system is unable to synthesize the carrier lipid undecaprenyl D-mannosyl phosphate. It was suggested that the juxtaposition of the mesosomal vesicles and the enveloping plasma membrane in vivo allows the mannan located on the mesosomal vesicles to accept D-mannosyl units from the carrier lipid located in the plasma membrane. 

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