Robinia lectin

Robinia lectin Robinia pseudoacacia (black Oligosaccharide... 

Lectins (proteins and/or glycoproteins of non-immune origin that agglutinate cells, from seeds of Robinia pseudoacacia), M 100,000. Purified by pptn with ammonium sulfate and dialysis then chromatographed on DE-52 DEAE-cellulose anion-exchanger, hydroxylapatite and Sephacryl S-200. [Wantyghem et al. Biochem J 237 483 1986.]... 

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). 

Stroma, erythrocyte membrane residues from haemolysed red cells, have been intra-crosslinked with glutaraldehyde and used for the affinity chromatographic purification of two nonspecific and noninhibitable lectins fi-om Phaseolus vulgaris and P. coccineus. Formaldehyde-fixed human erythrocytes have provided a specific adsorbent for the purification of the lectin from Robinia pseudocacia. ... 

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%. 

Occasionally the membrane is seen attached to cells in suspension culture (Fig. 5.1.2B). This membrane is associated with a variety of unusual structures containing phenolic residues and tannin. The role of these membranes or skins in osmotic phenomena, filtration, gas exchanges, lectin and enzyme partitioning, and energy transduction at or on surfaces is unknown. Lectins are associated usually with juvenile tissues, such as embryos and seeds, rather than with mature tissues (19, 20). However, lectins that bind manganese and zinc have been isolated from the bark of Robinia pseudoacacia (68). 

While the contribution of extracellular nitrogenous compounds is uncertain, preparations of poplar (Populus) sp. leaves have been used as a high-energy feed supplement for livestock (e.g., 36). Some preparations may contain toxic extracellular compounds. Lectins from Robinia pseudoacacia are toxic to mammalian cells, and have been explored as therapeutic agents in cancer patients (cf., 81, 88). 

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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