Hemagglutinating activity

A spectrophotometric assay was introduced by Liener.101 It is based on the observation that rabbit erythrocytes sediment at a rate proportional to the concentration of the hemagglutinin. Hemagglutinating activity is calculated from absorbance measurements at 620 nm of the unsedimented cell-suspension after a given time.97,101... 

Hemagglutinating activity in the common lentil (Lens culinaris or Lens esculenta) was first reported by Landsteiner and Raubitschek.439 Several laboratories have since isolated the lentil lectin in pure form, and studied its physical-chemical properties and interaction with carbohydrates.138,142,143,440 442... 

Metal analysis revealed one atom of Mn2+ and six atoms of Ca2+ associated with each 66.5 kg of protein.142 Addition of 5 mM Ca2+ and mM Mn2+ to the native lectins enhanced both hemagglutination and mannan precipitation. This indicates that either some metal loss occurred during purification, or that the metal binding-sites are never completely occupied442 (compare Refs. 300 and 301). Mn2+ stimulated the hemagglutinating activity of all lentil-lectin preparations more than did Ca2+, whereas Ca2+ promoted mannan precipitation more effectively.442 Demetallization, by dialysis against 0.1 M EDTA followed by M acetic... 

Dissociation of the phytohemagglutinin subunits was accompanied by a complete release of Mn2+ from the protein.444 Carbohydrate and Ca2+ remained bound to both subunits. Very low hemagglutinating activity was associated with the heavy subunit the light subunit was inactive. Addition of Mn2+ and Ca2+ to a mixture of H and L chains failed to restore hemagglutinating activity.444... 

Inasmuch as extensive maleylation of free amino groups did not abolish the hemagglutinating and polysaccharide-precipitating activity of the lentil lectin, it is probable that amino groups are not involved in the carbohydrate-binding site of the lectin.4473 Treatment of the lentil lectin with 1-acetylimidazole resulted in the modification of 3-5 tyrosyl and 7-17 amino groups.4473 The modified proteins had lost their hemagglutinating activity, but retained their capacity to interact with polysaccharides and to bind to erythrocytes.4473... 

A comparative study of the hemagglutinating activities of the pea (Pisum sativum), the lentil (Lens culinaris), and the jack-bean (Canavalia ensiformis) lectins towards the erythrocytes of fourteen different species showed446 that the pea and lentil lectins were, in all instances, more active than con A. Of great interest was the finding that, among these three lectins, con A alone was completely inactive against human erythrocytes (blood group, unspecified).446... 

Inhibition, by Various Sugars, of the Hemagglutinating Activity of the Potato (Solanum tuberosum) Lectin0... 

The specific-titer activity of lima-bean lectin components II and III towards type A human erythrocytes was 5,100 and 1,300, respectively, and, towards type B erythrocytes, 20 and 5.1, respectively.151 199 The hemagglutinating activity of component II is, thus, four times the activity151,199 of component III. Neither component reacted with type O human, red blood-cells, or native or trypsinized, rabbit erythrocytes.151,199... 

The blood-group H(O) specific hemagglutinating activity of Lotus tetragonolobus extracts was originally documented in the 1948 report of Renkonen6, and this was confirmed by others.22,77,78 In a landmark... 

Waller, G.R., Das Gupat, B.R., Smith, J.D. (1966). Estimation of toxic and hemagglutinating activity of ricin from... 

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