Publisher Summary Lectins play an important role in the development of immunology. Lectins also find application in serological laboratories for typing blood and determining secretor status, separating leucocytes from erythrocytes, and agglutinating cells from blood in the preparation of plasma. They serve as reagents for the detection, isolation, and characterization of carbohydrate-containing macromolecules, including blood-group antigens. In their interaction with saccharides, lectins serve as models for carbohydrate-specific antibodies, with the important advantage to purify lectins in gram quantities. Lectins are classified according to their carbohydrate-binding specificity that includes D-mannose(D-glucose)-binding lectins and 2-acetamido-2-deoxy-D-glucose-binding lectins. The chapter considers only those lectins that have been purified to homogeneity, and studied with regard to their biophysical, biochemical, and carbohydrate-binding specificity. The chapter also describes the cell-binding and biological properties of lectins. The chapter concludes with the description of several glycopeptide structures showing the carbohydrate-binding loci with which various lectins interact.

The lectins : carbohydrate-binding proteins of plants and animals

http://www.jbc.org/content/259/5/3308.full.pdf

Topography and polypeptide distribution of terminal N-acetylglucosamine residues on the surfaces of intact lymphocytes. Evidence for O-linked GlcNAc.

A rat monoclonal antibody specific for immunoglobulin (Ig) heavy chain binding protein (BiP) has allowed the examination of the association of BiP with assembling Ig precursors in mouse B lymphocyte-derived cell lines. The anti-BiP monoclonal antibody immunoprecipitates BiP along with noncovalently associated Ig heavy chains. BiP is a component of the endoplasmic reticulum and binds free intracellular heavy chains in nonsecreting pre-B (mu+, L-) cell lines or incompletely assembled Ig precursors in (H+, L+) secreting hybridomas and myelomas. In the absence of light chain synthesis, heavy chains remain associated with BiP and are not secreted. The association of BiP with assembling Ig molecules in secreting hybridomas is transient and is restricted to the incompletely assembled molecules which are found in the endoplasmic reticulum. BiP loses affinity and disassociates with Ig molecules when polymerization with light chain is complete. We propose that the association of BiP with Ig heavy chain precursors is a novel posttranslational processing event occurring in the endoplasmic reticulum. The Ig heavy chains associated with BiP are not efficiently transported from the endoplasmic reticulum to the Golgi apparatus. Therefore, BiP may prevent the premature escape and eventual secretion of incompletely assembled Ig molecules.

/pdf/posttranslational-association-of-immunoglobulin-heavy-chain-1w3rgq22ys.pdf

Posttranslational association of immunoglobulin heavy chain binding protein with nascent heavy chains in nonsecreting and secreting hybridomas.

The Biochemistry of glycoproteins and proteoglycans

https://pure.uva.nl/ws/files/4058964/2082_21713y.pdf

Architecture of the yeast cell wall. Beta(1-->6)-glucan interconnects mannoprotein, beta(1-->)3-glucan, and chitin.

http://www.jbc.org/content/246/21/6666.full.pdf

The Purification and Properties of the A Protein of Lactose Synthetase

Cross-linking of the components of lactose synthetase with dimethylpimelimidate.

Publisher Summary Agarose derivatives of monosaccharides are easily synthesized by reaction of cyanogen bromide-activated agarose with a monosaccharide derivative containing an amino function. Few naturally occurring monosaccharides contain an amino group, and those that have such a group are unlikely to yield satisfactory adsorbents when coupled to agarose. Usually it will be necessary to couple monosaccharides through a spacer so that they extend away from the agarose matrix. Thus, the major problem in preparation of a specific agarose adsorbent is the synthesis of the appropriate monosaccharide derivative. The affinity adsorbents prepared by coupling these types of ligands to agarose have been used successfully in the purification of enzymes and monosaccharide binding proteins. They appear to have a high degree of specificity, are sufficiently stable to withstand repeated use, and should find wide application in the future.

[29] Monosaccharides attached to agarose

Publisher Summary Nucleoside mono-, di-, and triphosphates and many of their derivatives, such as the sugar nucleotides and the vitamin-containing coenzymes, are substrates, inhibitors, or cofactors for a wide variety of enzymes. Thus, nucleotide phosphates attached to agarose should have wide application as affinity adsorbents for the purification of many different enzymes. Derivatives of nucleoside phosphates containing a primary amino group can be coupled readily to cyanogen bromide-activated agarose. The major problem in preparation of the adsorbents is the design and synthesis of the nucleotide ligands to be attached to agarose. At present, four kinds of ligand (1, 2, 3, and 4) have been synthesized containing an alkyl or aryl-amino group attached to the phosphate, the purine base, or the ribosyl ring of the nucleotide.

Ian P. Trayer

Papers

The Purification and Properties of the A Protein of Lactose Synthetase

Cross-linking of the components of lactose synthetase with dimethylpimelimidate.

[29] Monosaccharides attached to agarose

Nucleoside phosphates attached to agarose.

The structure, function, and evolution of alpha-lactalbumin.