[Preparation of biologically transformed raw material from woolly foxglove Digitalis lanata Ehrh and isolation of digoxin from it].

A biotechnological approach is proposed for conservation of a terraneous part of woolly foxglove under anaerobic conditions with a subsequent air-sun drying of the biologically transformed raw material. During the conservation primary foxglove glycosides completely convert to secondary ones which do not transform further. A simple method is described for preparation from the transformed raw material of an enriched glycoside fraction with the yield of 3.

[Glycosylation of glycoconjugates on thymocyte surfaces].

The ectosialation and ectogalactosylation of mouse thymocyte surface were studied. The incorporation of labeled monosaccharides (N-acetylneuraminic acid and galactose) into cell surface glycoproteins and glycolipids were demonstrated. Identification of glycolipids was carried out.

[Fluorescent derivatives of carbohydrates in the analysis of the structure of glycoconjugates. N-(4-methylcoumarin-7-yl) glycamines in the study of asparagine-bound carbohydrate chains of glycoproteins].

4-(N-Methylcoumarin-7-yl) glycamines were employed in studying asparagine-linked carbohydrate chains of acid desialylated fetuin. The procedure was optimised for the reductive amination of oligosaccharides with 7-amino-4-methylcoumarin in the presence of Na(CN)BH3 to lead to oligosaccharide glycamines (AMC-OS). AMC-OS were obtained from dextran oligosaccharides and from oligosaccharides released by hydrazinolysis of asparagine-linked sugar chains of asialofetuin.

[Isomerization of trifluoroacetamidopropyl-2-acetamido-2-deoxy-D- galactopyranoside into alpha-anomer. A convenient method of synthesis of the artificial T-antigen].

Bioside Gal beta 1-3GalNAc alpha 1-O(CH2)3NHCOCF3 has been synthesized. The key alpha-glycoside GalNAc alpha 1-O(CH2)3NHCOCF3 (peracetate) was obtained either by isomerization of its beta-anomer with trifluoromethanesulfonic acid, or by direct glycosylation of 3-(trifluoroacetamido)propanol with D-galactosamine (anomeric pentaacetate) in the presence of a mixture of trifluoromethanesulfonic acid and boron trifluoride etherate. De-O-acetylated alpha-galactosaminide obtained was further transformed into benzylidene derivative, the latter was glycosylated with acetobromogalactose to give the protected alpha-bioside.

[Artificial peptide and carbohydrate antigens. Immobilization of haptens and adjuvant (MDP) on polyacrylamide].

To study the influence of the polyacrylamide carrier on immunogenic properties of the peptide and oligosaccharide haptens, we have prepared artificial antigens by conjugation of a synthetic hexapeptide (homologous to the fragment 95-100 of the murine H-2Db antigen heavy chain) or of an oligosaccharide (antigenic determinant of human blood groops, Lea) with polyacrylamide. In some cases the conjugates containing also a synthetic glycopeptide adjuvant, N-acetylmuramoyl-L-alanyl-D-isoglutamine (MDP), were used. Antisera against haptens were obtained by immunization of BALB/c mice with corresponding conjugates.

[Monospecific antibodies against synthetic T-antigen. Characteristics of their specificity and use in the identification of T-antigenic determinants on the cell surface].

Monospecific antibodies directed to a Thomsen-Friedenreich antigen (T-antigen) were obtained using artificial antigen. T-antigen immunodominant alpha-disaccharide Galbeta (1----3) GalNAc alpha 1-(T alpha) and its beta-anomer Gal beta (1----3) GalNAc beta 1-(T beta) were bound to bovine serum albumin (BSA) and cytochrome C (CCC) through a spacer (sp = -O(CH2)3NHCO (CH2)4CO-) by the azide method to give neoglycoproteins T alpha-sp-BSA, T alpha-sp-CCC and T beta-sp-BSA. Anti-T alpha antiserum was obtained by immunization of rabbits with T alpha-sp-BSA and then purified by sequential affinity chromatography on BSA-Sepharose and T alpha-sp-BSA-Sepharose to yield monospecific anti-T IgG antibodies.

[A convenient synthon for the synthesis of the determinant oligosaccharides Le and ABH (type 1)].

Precursors of blood group oligosaccharides ABH (type 1) and Le have been synthesized starting from benzyl 2-acetamido-3-O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-6-O-ben zyl-2- deoxy-alpha-D-glucopyranoside after simple blocking and deblocking steps. The above disaccharide was prepared by regioselective galactosylation of benzyl 2-acetamido-6-O-benzyl-2-deoxy-alpha-D-glucopyranoside under Helferich conditions in 69% yield.

[Synthesis of determinant oligosaccharides of the ABH (type 1) blood group antigen and Leb tetrasaccharide from a common precursor].

Synthesis of blood group ABH (type 1) determinant oligosaccharides and Leb tetrasaccharide has been performed using the same trisaccharide precursor-benzyl 2-acetamido-4,6-O-benzylidene-[4,6-O-benzylidene-2-O-[2-O-benzyl-3,4-di- O- (4-nitrobenzoyl)-alpha-L-fucopyranosyl]-beta-D-galactopyranosyl]-2-deoxy - alpha-D-glucopyranoside. A- and B-determinants were prepared by alpha-galactosaminylation and alpha-galactosylation of the title trisaccharide, respectively. Leb-determinant was synthesized by a series of simple blocking and deblocking steps followed by alpha-fucosylation.

[Glycoproteins of tumor and normal tissue of the human breast].

Antigenic preparations from human tumour (TMG) and normal mammary gland (NMG) tissues were isolated, using water extraction followed by precipitation of proteins with perchloric acid, which were further separated into fractions A, B and C by gel filtration on Sepharose 6B. Glycoprotein fractions B and C were further separated by IEC on DEAE cellulose to give fractions B1-BIV and C1-CIV. A set of glycoproteins (Mr = 13 000-122 000; pI approximately 3-7.

[Purification and properties of beta-galactosidase from Alternaria tenius].

beta-Galactosidase from Alternaria tenius was purified to homogeneity from the cultural fluid using acetone precipitation, ion-exchange chromatography on DEAE-cellulose, adsorption on hydroxylapatite and affinity chromatography on N-(beta-D-galactopyranosyl-thiocarbamoyl)-beta-aminocaproyl-AN-Sepharose 4B. The enzyme homogeneity was demonstrated by ultracentrifugation and polyacrylamide gel electrophoresis with SDS or without it. The specific activity of the homogeneous enzyme is 160 u.

[Properties of membrane-bound sialyltransferase from rana temporaria liver].

It was demonstrated that microsomal membranes from frog liver contain at least two different sialyltransferases involved in the synthesis of alpha 2 leads to 3 and alpha 2 leads to 6 oligosaccharide isomers. Studies on acceptor specificity of the sialyltransferase system with respect to low molecular acceptors revealed its similarity to the mammalian sialyltransferase system. However, sharp distinctions were observed in sialylation of mammalian glycoproteins.

[Lysosomal neuraminidase, beta-galactosidase and beta-N-acetylglucosaminidase of regenerating liver tissue].

Neuraminidase (EC 3.2.1.

[Soluble and membrane-bound neuraminidase in regenerating rat liver].

Two forms of neuraminidase (soluble and membrane-bound) are found in regenerating rat liver. Specific activity of the soluble form was found to be maximal in 18 hours after partial hepatectomy, and that of the membrane-bound form-in 24 hours after the operation. Maximal specific activities of both neurominidase forms from regenerating rat liver considerably exceeded that from intact rat liver, shem-operated liver and also from embryonic and lactating rat liver.