Artículo W. Jaffe Isolation and partial characterization of bean phytohemagglutinins*

Extracts of seeds of 21 bean cultlvars were screened for hemagglutinating specifity and for mitogenic activity. Four types could be distinguished in different beans, two of which are mitogens. Two lectin fractions (α and b) were isolated from each of the four bean types. Their MW were estimated by exclusion chromatography and component sugars by paper chromatography. Hemagglutinating activity, inhibition of hemagglutinating action by sugar-derivatives and glyco-peptides as well as mitogenic action were determined for the eight purified lectins and four control preparations. The α and b-fractions isolated from two bean types had only minimal mitogenic action, while those from the other two bean types and all of the control preparations were potent mitogens. All the mitogenic preparations agglutinated trypsinactivated cow red blood cells and pronase-activated hamster red blood cells in high dilutions but some were inactlve when tested with human or rabbit red blood cells. An Venez Nutr 2015; 28(1): 74-81. Key Word Index: Phaseolus vulgaris, leguminosoae, beans, lectins, phytohemagglutinins, glycoproteins, lymphocyte stimulation.