Proteins lectin

Gorelik E, Galili U, Raz A. On the role of cell surface carbohydrates and their binding proteins (lectins) in tumor metastasis. Cancer Metast Rev 2001 20 245-277. 

Phase transition in gels in response to biochemical reactions [27,28]. Polymer gels were synthesized in which an enzyme (urease) or a biologically active protein (lectin) was immobilized. The volume phase transitions were observed in such gels when biochemical reactions took place. Such mechano-biochemical gels will be used in devices such as, sensors, selective absorbers, and biochemically controlled drug release. 

Polypeptides are substrates for receptor-mediated transcytosis. Cerebral insulin reaches the brain from the circulation via receptor-mediated transcytosis through the BBB on the brain endothelial insulin receptor. This receptor is upregulated in development and downregulated in streptozotocin-induced diabetes mellitus. Similarly a BBB transferrin receptor mediates the transcytosis of transferrin across the BBB and this explains how the brain is able to extract iron from the circulation. Other RMT pathways consituting portals of entry to the brain for circulating peptides include receptors for insulin-like growth factors, cationic proteins, lectins, acetyl-low density lipoprotein and leptin. 

Some of the proteins are toxic in nature. Ricin present in castor bean is extremely toxic to higher animals in very small amounts. Enzyme irvhibitors such as trypsin inhibitor bind to digestive enzyme and prevent the availability of the protein. Lectin, a toxic protein present commonly in legumes, agglutinates red blood cells. A bacterial toxin causes cholera, which is a protein. Snake venom is protein in nature. 

Hopefully, different variations of the methodology presented here may lead to biologically important oligosaccharides, help establish enzyme speciHcities, and give access to affinity absorbents for use in isolation of saccharide-binding proteins, such as antibodies, myeloma proteins, lectins, and enzymes. 

DNA-binding proteins, lectins, lipids, carbohydrates, and estimation of binding constants and weak interactions. 

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