Lectin function

PROTEOLYTIC ACTIVITY. In comparison with pancreatic trypsin, acrosin is 50% larger, contains carbohydrate, and is more hydrophobic (11). Although acrosin has often been referred to as trypsin-like, the above structural differences are reflected in kinetic and hydrolytic specificity differences, in different interactions with membranes, and in the newly described lectin function of acrosin. 

Brack A, Abu-Dahab R, Borchard G, et al. Lectin-functionalized liposomes for pulmonary drug delivery interaction with human alveolar epithelial cells. J Drug Target 2001 9 241. 

Abu-Dahab R, Schafer UF, Lehr CM. Lectin-functionalized liposomes for pulmonary drug delivery effect of nebulization on stabUity and bioadhesion. Eur J Pharm Sci 2001 14 37-41. 

Leong, K.H., Chung, L.Y., Noordin, M.I., Onuki, Y., Morishita, M., Xakayama, K. Lectin-functionalized carboxymethylated kappa-cturageenan microparticles for oral insulin delivery. Carbohydr. Polym. 86(2), 555-565 (2011)... 

Most considerations of plant lectin function revolve around the carbohydrate binding activities of these proteins. Yet, as discussed in a previous section of this chapter, additional activities are associated with some of these lectins. These activities must also be taken into account in considering the possible roles of these proteins. For example, a major class of plant hormones, the cytokinins, are derivatives of adenine that bind with high affinity to the hydrophobic binding sites found on some of the legume seed lectins and at least one seed-like vegetative tissue lectin [20, 30]. It is of interest that the specificity of this site, when present, appears to have... 

LECTINS CAN BE USED TO PURIFY GLYCOPROTEINS TO PROBE THEIR FUNCTIONS... 

Glycophorin A appears to serve a variety of functions on the red-cell membrane, and has been implicated in several red-cell disorders. Because it extends from the external environment of the cell into the cell cytoplasm, it is considered to constitute a receptor for malarial parasites,"" influenza viruses, lectins, and Portuguese man-of-war toxin. Many of these receptor functions are attributable to the carbohydrate composition of these... 

A wide diversity of herbal remedies have purported abilities to stimulate defense functions. Complexes of carbohydrate and lignin, which are present in some herbs, modulate enteric immune functions (Kiyohara et al, 2000), and the changes in cytokine secretion (Matsumoto and Yamada, 2000) can trigger systemic responses. The polysaccharides present in other herbal medicines augment production of immunoglobulin (Ig) A by the Peyer s patches in the small intestine (Sakushima et al, 1997 Yu et al, 1998). The responses of the enteric immune system to lectins are variable (Pusztai 1993), and can elicit systemic responses (Lavelle et al, 2000). Other phytochemicals provide protection by inducing detoxification pathways in mucosal cells (Williamson et al, 1998). 

KiMURA T, NAKATA s, HARADA Y, YOSHIDA A (1986) Effect of ingested winged bean lectin on gastrointestinal function in the rat. JNutr Sci Vitaminol (Tokyo). 32 101-10. 

PUSZTAI A (1993) Dietary lectins are metabolic signals for the gut and modulate immune and hormone functions. Eur J Clin Nutr. 47 691-9. 

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