Recombinant Fragment of the Extracellular Domain of Human Desmoglein 3 Fused with the Fc-Fragment of Human IgG1 Selectively Adsorbs Autoreactive Antibodies from the Sera of Pemphigus Patients.

Using the recombinant second fragment of the extracellular domain (EC2) of human desmoglein type 3 (Dsg3) as an affinity ligand, an immunosorbent was obtained that selectively binds autoreactive antibodies to this domain from the immune sera of patients with pemphigus. The EC2 protein was obtained in the form of a fusion protein with the Fc-fragment of human IgG1. The production was carried out in CHO cells using the method of transient expression.

[Synthesis of somatostatin in Escherichia coli cells: isolation and characteristics]. / Sintez somatostatina v kletkakh Escherichia coli. Vydelenie i kharakteristika.

A synthetic gene coding for somatostatin-14 (SST) was cloned in plasmid expression vectors in frame with the chloramphenicol acetyl transferase (CAT) gene, both genes being divided by a Met residue. The hybrid gene was expressed under the control of the CAT gene promoter (Pcat) or the tryptophan operon promoter (Ptrp). Them fused genes gave insoluble polypeptide products amounting from 5% of the total cellular protein under constitutive biosynthesis conditions (Pcat) to 30% upon induction (Ptrp). SST was liberated from the fused polypeptide by treatment with cyanogen bromide, purified to homogeneity by gel-filtration and reverse phase HPLC, and finally refolded by dilution and air oxidation. The renaturated recombinant SST showed the specific biological and immunological activities of the native peptide.

[Certain biochemical characteristics of an insulin-like substance from the bivalve mollusk Anodonta cygnea]. / Nekotorye biokhimicheskie kharakteristiki insulinopodobnogo veshchestvadvustvorchatogo molliuska Anodonta cygnea.

An insulin-like substance (ILS) was isolated from the visceral organs of the bivalve mollusc Anodonta cygnea by chromatography on a sulfocationite CU-23 and purified by reverse phase liquid chromatography. ILS was shown to be made up to several fractions with Mr ranging from 9 to 20 kDa which have identical amino acid composition but different hydrophobicity and N-terminal amino acids. It was supposed that the heterogeneity of ILS fractions is due to its genetical or posttranslational polymorphism. ILS has a low (0.02%) affinity for the mammalian insulin receptor and a low immune affinity for mammalian insulin and possesses a mitogenic activity which is commensurate with that of the epidermal growth factor. The data obtained suggest that Anodonta cygnea ILS represents a separate branch of a relatively ancient family of insulin-like hormones and growth factors responsible for metabolism and proliferation of invertebrate tissues.

[Isolation and properties of specific trypsin inhibitor from human seminal plasma]. / Vydelenie i svoistva spetsificheskogo ingibitora tripsina iz semennoi plazmy cheloveka.

Gel filtration of human seminal plasma on Sephadex G-100 revealed four zones displaying the activity of trypsin inhibitors. The inhibitor from the zone corresponding to the molecular mass of 30-40 kDa was obtained in an electrophoretically homogeneous form. The purification procedure included gel filtration on Sephadex G-100, anion-exchange chromatography on DEAE-Sephadex A-50, ammonium sulfate precipitation and hydrophobic chromatography on phenyl-Sepharose 4B. The inhibitor thus obtained has a specific activity of 1.29 IU/mg protein in a caseinolytic test, molecular mass of about 36 kDA and pI of 7.2. The glycosidase and lectin analysis of the carbohydrate component of the protein revealed the presence of neuraminic (sialic) acid and galactose (galactosamine). The amino acid composition of the protein was determined. Antibodies to this protein were obtained; the high specificity of the protein for human sperm was demonstrated The inhibitor was found to be immunochemically identical to previously described prostatic beta-globulin.

Isolation, primary structure, and biological and immunological properties of pink and chum salmon insulins.

1. Insulins have been isolated from islet tissue of pink (Oncorhynchus gorbuscha) and chum (Oncorhynchus keta) salmon. The primary structure of chum and pink salmon insulins was found to be identical. Compared to the amino acid sequence of human insulin, the salmon insulins under study differed at 14 positions. 2. Biological activity of pink salmon insulin was 83% of that of standard porcine insulin. 3. The immunological properties of fish insulins were investigated in specific radioimmunoassay (RIA) systems, based on porcine and pink salmon insulins. 4. A significant difference in the antigenic determinants of these fish and mammalian hormones was revealed.

[Amino acid sequence of the insulin of the dog salmon Oncorhynchus keta]. / Aminokislotnaia posledovatel'nost' insulina kety Oncorhynchus keta.

It has been demonstrated that A-chain of insulin in the salmon O. keta consists of 21 amino acid residues with N-terminal glycine and C-terminal asparagine. B-chain is formed by 29 residues with alanine and lysine as N- and C-terminals correspondingly.

[Luteinizing hormone of the sperm whale. Amino acid sequences of reduced and carboxymethylated beta-subunits]. / Liuteiniziruiushchii gormon kashalota. Aminokislotnaia posledovatel'nost' vosstanovlennoi i karboksimetilirovannoi beta-sub"edinitsy.

The amino acid sequence of reduced and carboxymethylated beta-subunit of the luteinizing hormone of the sperm-whale was established. The beta-subunit was found to consist of 118 amino acid residues, the N- and C-terminal amino acids being proline and leucine, respectively. The carbohydrate moiety is linked to the asparagine residue at position 13.

[Luteinizing hormone of the sperm whale. Isolation, separation into subunits and study of the amino acid sequence of the alpha-subunit]. / Liuteiniziruiushchii gormon kashalota. Vydelenie, razdelenie na sub"edinitsy i izuchenie aminokislotnoi posledovatel'nosti al'fa-sub"edinitsy.

The luteinizing hormone isolated from sperm-whale pituitary was separated into two subunits, alpha- and beta-, by ion-exchange chromatography on sulfoethyl-Sephadex. The hormone subunits were reconstituted, carboxymethylated and cleaved by BrCN and proteolytic enzymes. In order to block tryptic hydrolysis at lysine residues the alpha-subunit was subjected to maleylation. Large-sized fragments of BrCN were cleaved by chymotrypsin and trypsin, while large-sized fragments of trypsin were split by chymotrypsin. The resulting peptides were separated by gel filtration on Sephadex, ion-exchange chromatography on Aminex A-5 and thin-layer partition chromatography on cellulose. The amino acid sequence of the peptides was determined by the Edman method, using identification of the N-terminal amino acids in a reaction with dansyl chloride or dimethylaminoazobenzene-4-isothiocyanate. It was shown that the alpha-subunit of the luteinizing hormone is a peptide chain consisting of 96 amino acid residues with covalently linked carbon chains at asparagine residues at positions 56 and 82. The N-terminal amino acid of the alpha-subunit is phenylalanine, the C-terminal amino acid is serine. The alpha-subunit is heterogeneous at the N-end, i. e. beside phenylalanine it contains threonine and trace amounts of proline, aspartate, glutamate and glycine.