Black-locust lectin

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... 

Robinia pseudoacada, the black locust (Fabaceae), is a common cultivar in the United States and in Europe and is commonly escaped from cultivation. The bark contains several toxic proteins (Kingsbury, 1964). The seeds are also known to contain a distinct lectin (Liener et al, 1986). 

Proteins and their derivatives, especially the lectins, extracellular to the cell wall, are now a common observation (Tables 5.1.1 and 5.1.2). Lectins from the bark of black locust (Robinia pseudoacacia) have been isolated by specific absorption on formaldehyde-fixed human erythrocytes and eluted with a borate solution (68). The lectin is homogeneous on disc electrophoresis and yields three bands on isoelectric focusing. It has a molecular weight of s 110000 and consists of two subunits (MW 29000 and 31500). Its pi is 5.9 and it contains large amounts of aspartic acid, threonine, and serine, no cysteine, and very little methionine. Covalently bound neutral sugar constitutes 7.2% of the structure and glucosamine constitutes 0.47%. 

Hofejsi V, Haskovec C, Kocourek J 1978 Studies on lectins. XXXVIII. Isolation and characterization of the lectin from black locust bark Robinia pseudoacacia L). Biochim Biophys Acta 532 98-104... 

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