Potato lectin isolation

The hydroxy-L-proline of the crude, mung-bean-wall preparation is not associated with the lectin259 this indicates a difference between the mung-bean-wall lectin and the lectin isolated from potato tubers. The latter is rich in hydroxy-L-proline, arabinose, and galactose260 in this respect, it shows features similar to those of the hydroxy-L-proline-rich glycoprotein ( extensin ) of the primary cell-wall, first reported by Lamport261 (see Section VII, 1). 

The work of Owens and Northcote (1981) has produced convincing evidence that the Golgi apparatus is the site of assembly of these sequences and that similar mechanisms operate to assemble them in potato lectin and cell wall glycoproteins. What is now needed is a search for lipid-linked intermediates and the isolation and characterisation of the transferases involved. 

Although seeds are the common source of lectin activity, there are reports (some contradictory) of agglutinins occurring in leaves, stems, and roots.77,94 For example, black-locust (Robinia pseudoaccacia) lectin160 was isolated from its bark, potato (Solanum tuberosum) lectin161 from its tubers, and poke-weed (Phytolacca americanum) mitogen162 from its roots. A new class of plant cell-wall and membrane-bound lectins ( /3-lectins ) has been described.116,163,164 A treatise collected several schemes for the purification of lectins.165,1658... 

A true lectin which was isolated from potato tubers and shown to bind N-acetyl glucosamine residues was the first lectin demonstrated to contain hydroxyproline (6). Allen and Neuberger (6) showed that the potato tuber lectin is composed of 50% protein and 50% carbo-... 

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