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1978 (1)
1972 (1)
1Author    G. Uhlenbruck, A. RadunzRequires cookie*
 Title    Use of Heterophilic Agglutinins in Plant Serology  
 Abstract    In previous communications it has been demonstrat-ed that monogalactosyl diglyceride and the anionic chloroplasts lipids can be detected on the thylakoid membrane by specific antisera 1_3 . The antigen deter-minants are of carbohydrate nature as was shown by specific agglutination inhibition tests. They are located on the outer surface of the thylakoid membrane and are directly accessible to the antibodies. The latter has been proven for the monogalactolipid 1 , whereas the de-terminants having the carbohydrate structure like that of sulphoquinovosyl diglyceride 2 stick out of the sur-face like phosphatidyl glycerol too 3 , but are topogra-phically rather arranged in gaps or pores of the membrane. Fatty acids are not involved in this antigen-antibody reactions as precipitation studies with hydrat-ed lipids and with lipids of different fatty acid com-positions have revealed. On the other side, if sugar components represent the immunologically determinant groups, then it should be possible to confirm the results obtained with vertebrate antisera by using heterophilic agglutinins from plants (so-called lectins) 4 , inverte-brates and fish eggs. These are known to be excellent tools for the specific detection of terminal and inner-chain carbohydrate structures of different configurations and conformations 5 . As D-galactose is the main deter-minant sugar in plant glycolipids, we tested some of the galactose specific lectins in our system. It could be found, that the agglutinin from Ricinus communis, the anti-galactosyl specificity of which is well established 4 , agglu-tinated chloroplasts and thylakoidfragments in a very specific way. This agglutination was inhibited by 0.03 M D-galactose, 0.06 M lactose, raffinose, stachyose, mono-galactosyl glycerol (/9-glycosidic linkage), and digalac-tosyl glycerol (a-glycosidic linkage of D-galactose), but not by D-glucose, and L-arabinose. In addition, the spe-cific anti-a-galactosyl agglutinin 6 ("anti-B") from Salmo trutta (trout) also reacts well, especially after protease treatment. It is inhibited by carbohydrates with terminal a-glycosidic bound D-galactose (raffinose, stachyose, digalactosyl glycerol 0.03 M) and not by monogalactosyl glycerol, lactose, D-glucose, D-and L-arabinose. We got weaker reactions with agglutinins from fungal origin like Fomes fomentarius, a lectin known as anti-B (a-galactosyl) reagent 4 ' 7 , whereas other agglutinins (Arachis hypogoea "anti-T") directed to D-galactose-like structures 8 gave very weak 
  Reference    (Z. Naturforsch. 27b, 1113 [1972]; received June 27 1972) 
  Published    1972 
  Keywords    Heterophilic agglutinins, glycolipids, chloroplasts, thylakoids, lectins 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-1113_n.pdf 
 Identifier    ZNB-1972-27b-1113_n 
 Volume    27 
2Author    G. Uhlenbruck, B. P. Chatterjee, U. SchuldesRequires cookie*
 Title    Schiff Base Form ation: Dem onstrated by a Precipitin Reaction in A g a r  
 Abstract    High-m olecular weight polyaldehydes, which can be o b ­ tained by periodate oxidation of glycosubstances, especially polysaccharides, do precipitate in a specific way by Schiff base formation, when diffusing in agar gel against high-m olecular weight, naturally occurring polyamines. album (m istletoe), R icinus com m unis and from the bivalve clam Tridacna m axim a (see Fig. l a) . Also the plant lectins from Ononis spinosa and Abrus precatorius do give such a precipitin reaction. This precipitation phenomenon however is abolished, when the terminal D-galactose (/?-l-6 linked) has been oxidized by sodium periodate (F ig . l b) , whereas the precipitin reaction due to Schiff base form ation does not occur with the genuine, un­ treated arabinogalactan (F ig . 1 a) . N egative reac­ tions are also seen after borohydride reduction or by blocking the carbonyl groups (o r the amino groups) by other methods [ 1 1 ] *. Oxidation o f lymphocytes from a variety of spe­ cies with either sodium periodate, galactose-oxidase or neuraminidase and galactose-oxidase induces blastogenic transformation [ 1 — 5 ], or lymphocyte cytotoxicity [ 6]. In addition, tumor cell killing occurs, when by the same procedures artificial con­ tacts are established between normal macrophages and tumor cells [ 7 ]. Although these intriguing phenomena are not yet completely elucidated, it is assumed that cross-linkages via Schiff bases play an important role [6 — 8]. The only evidence for this hypothesis is given by the fact, that sodium b oro­ hydride treatment abolishes the effect. It was there­ fore desirable, to have an in v itro model for the form ation o f Schiff bases in order to study the inter­ action o f different membrane glycosubstances and proteins. A s standard materials for developing a representative precipitin experiment we have first chosen periodate-treated arabinogalactan from plant origin [9 ] and polylysine as amino group donator [10]. In Fig. 1 it is demonstrated, that Schiff base fo r ­ mation between these two components indeed can be made visible in form o f a precipitation line. In addition, b iological substances with free amino groups, like histone [ 10], lysozyme [ 10] and haem oglobin [1 1 ] react in a similar way (F ig . 1 b), while a synthetic basic polym er without any amino groups, namely polybrene [ 10], does not pre­ cipitate as has been found by us. On the other hand, genuine arabinogalactan precipitates with some anti-galactosyl specific lectins like the one from Viscum 
  Reference    Z. Naturforsch. 33c, 442 (1978); received February 2 1978 
  Published    1978 
  Keywords    Basic Polyam inoacids Periodate-Treatment, Arabino-galactan, Lectins, Cell Aggregation 
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 TEI-XML for    default:Reihe_C/33/ZNC-1978-33c-0442_n.pdf 
 Identifier    ZNC-1978-33c-0442_n 
 Volume    33