Hemagglutinin lectin

Some legumes, including raw soy or peanut flour are known to contain certain antinutritional factors such as proteinase inhibitors and hemagglutinins or lectins (21,22). These factors can be inactivated, for the most part, by moist heat, during processing. Interestingly, peanut flour contained more trypsin inhibitor and lectin than did soy flour (22). 

Plant lectins (also termed agglutinins, hemagglutinins, and phytohemagglutinins) are glycoprotein macromolecules that are capable of specific, noncovalent binding to carbohydrates.489 Lectins are known to occur widely in the seeds of plants488 however, they have also been... 

In order to prevent infection, for example, with an influenza virus, it is necessary to block at least one out of two of the substances present on its surface One of them is a neuraminidase, an enzyme that cleaves off sialic acid, and the other is a hemagglutinin, a sialic acid-specific lectin which aids the influenza viruses in docking onto oligosaccharides exposing sialic acid on the surface of host cells. Both compounds are prerequisite for the infection process. 

Lectins (hemagglutinins) in raw soybeans can inhibit growth and cause death in animals. They are proteins that bind to carbohydrate-containing molecules and cause blood clotting. Fortunately lectins are degraded rapidly by heating. Soybeans also contain growth inhibitors that are not easily deactivated by heat treatment. 

In common with many other legume seeds, raw lentils contain some undesirable constituents, although the levels of these are not likely to be of concern in poultry feeding. Weder (1981) reported the presence of several protease inhibitors in lentils. Marquardt and Bell (1988) also identified lectins (hemagglutinins), phytic acid, saponins and tannins as potential problems but could find no evidence that these had adversely affected performance of pigs fed lentils. It is known that cooking improves the nutritive value of lentils for humans but the effects of consumption of raw lentils by non-ruminants have not been well documented (Castell, 1990). 

Hemagglutinins may be of several types (a) nonspecific lectins that agglutinate cells without regard to their origin (either species, or blood type), (b) lectins that preferentially agglutinate the cells of one or several kinds of animals, or (c) blood-group-specific lectins. 

Interestingly, Matsumoto and Osawa196 reported that p-nitrophenyl (and phenyl) 2-acetamido-2-deoxy-/3-D-glucopyranoside, at a concentration of 10 mg/ml, did not inhibit the agglutination reaction between the potato lectin and human erythrocytes, whereas both p-nitrophenyl 2-acetamido-2,6-dideoxy-/3-D-gIucopyranoside and phenyl 2-acet-amido-3-0-(D-l-carboxyethyl)-2-deoxy-j3-D-glucopyranoside, at a level of 5 mg/ml, completely inhibited the hemagglutinin reaction. The... 

Analysis showed that the snail agglutinin contained a preponderance of acidic and hydroxylic amino acids and a large proportion of proline residues.83,560-562 Uncharacteristic of lectins from leguminous-plant seeds, the hemagglutinin contained 18 half-cystine residues and 10 molecular proportions of methionine per molecule of protein.83,569 About 8% (by weight) of covalently bound carbohydrate was found this was principally D-galactose and D-mannose.63... 

Cell-binding studies on human erythrocytes, several human, urinary-bladder, carcinoma cell-lines, and an osteogenic-sarcoma cellline have been conducted.189 After treatment with neuraminidase, 80% of human lymphocytes will bind the H. pomatia lectin.5728 Neuraminidase-treated lymphocytes can also be fractionated on Helix pomatia hemagglutinin coupled to Sepharose beads.572b... 

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