title: Influence of nucleic acids and polysaccharides on phosphotransferase activity of preparations of secretory immunoglobulin A from human milk.
abstract: The influence of nucleic acids (DNA, tRNA), synthetic oligonucleotides, and polysaccharides (lipopolysaccharides from Escherichia coli, heparin) on protein kinase and lipid kinase activities of preparations of human secretory immunoglobulin A (sIgA) has been studied. The preparations of sIgA were isolated from human milk by chromatography on the column with Protein A-Sepharose and DEAE-sorbent (sIgA1), by affinity chromatography of sIgA1 on DNA-cellulose (sIgA2), and by gel-filtration of sIgA1 in buffer containing 5% dioxane (sIgA3). Two 32P-labeled products with high and low electrophoretic mobility in polyacrylamide gel containing SDS were found after incubation of sIgA1 and sIgA2 with [gamma-32P]ATP. The product with low electrophoretic mobility was degraded in 10% trichloroacetic acid giving a radioactive background in lanes of the polyacrylamide gel. 32P-Labeled phospholipids were found among the phosphorylation products. Soluble and immobilized DNA increase lipid kinase activity of preparations of sIgA. In this case the secretory component and H-chains of sIgA were degraded. Fractions possessing lipid kinase activity were precipitated in the presence of heparin (1 mg/ml), and lipid kinase activity was separated from sIgA by gel-filtration in buffer containing 5% dioxane. 32P-Labeled products were formed in the presence of [gamma-32P]ATP as well as [32P]ortho-phosphoric acid. The influence of heparin and synthetic deoxy- and ribooligonucleotides on casein kinase activity of sIgA3 was studied. It was observed that deoxyribooligonucleotides in micromolar concentrations increased the rate of casein phosphorylation in the presence of sIgA3 and [gamma-32P]ATP. It has been proposed that catalytically active sIgA have an affinity to DNA (anti-DNA sIgA) and can be present in human milk as a part of lipoprotein complexes.
authors.affiliation: Novosibirsk Institute of Bioorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia. kit@niboch.nsc.ru.
authors.forename: Y Y
authors.initials: YY
authors.lastname: Kit
authors.forename: D V
authors.initials: DV
authors.lastname: Semenov
authors.forename: E V
authors.initials: EV
authors.lastname: Kuligina
authors.forename: V A
authors.initials: VA
authors.lastname: Richter
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D000974:Antibodies, Antinuclear / Q000302:isolation & purification / Q000378:metabolism; D002417:Cattle; D004247:DNA / Q000494:pharmacology; D005260:Female; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000302:isolation & purification / Q000378:metabolism*; D066298:In Vitro Techniques; D008070:Lipopolysaccharides / Q000494:pharmacology; D008074:Lipoproteins / Q000302:isolation & purification / Q000378:metabolism; D008894:Milk Proteins / Q000302:isolation & purification / Q000378:metabolism; D008895:Milk, Human / Q000201:enzymology* / Q000276:immunology*; D009696:Nucleic Acids / Q000494:pharmacology; D010770:Phosphotransferases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D000974:Antibodies, Antinuclear; D007071:Immunoglobulin A, Secretory; D008070:Lipopolysaccharides; D008074:Lipoproteins; D008894:Milk Proteins; D009696:Nucleic Acids; D000255:Adenosine Triphosphate; D006493:Heparin; D004247:DNA; D010770:Phosphotransferases