ABSTRACT
The restriction-modification system, named RMMunI, has been purified and characterised from Friend murine erythroleukemia cells. The site-specific endonuclease recognizes and cleaves the 5'C1AATTG nucleotide sequence. RMunI is an isoschizomer of RMfeI from Mycoplasma fermentans. Site-specific methylase modifies the second adenine residue in the same sequence (5'Cam6ATTG). It was established that the discovered enzymatic system is from mycoplasma which contaminates cell lines. Mycoplasma's DNA hybridizes with species-specific DNA probed for Mycoplasma fermentans and Mycoplasma arginini. The possible role of mycoplasmic restriction-modification enzymes in the process of acquired immune deficiency syndrome are discussed.
Subject(s)
Deoxyribonucleases, Type II Site-Specific/metabolism , Mycoplasma fermentans/enzymology , Acquired Immunodeficiency Syndrome/enzymology , Animals , Bacteriophage lambda/metabolism , Base Sequence , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , DNA, Viral/metabolism , Deoxyribonucleases, Type II Site-Specific/isolation & purification , Electrophoresis, Agar Gel , Leukemia, Erythroblastic, Acute/enzymology , Mice , Molecular Sequence Data , Tumor Cells, CulturedABSTRACT
The work presents the results of experimental study of gamma interferon obtained by gene engineering techniques on the basis of Escherichia coli producer strains. The study has revealed that gamma interferon, whose molecular weight is 15 KD, due to intracellular proteolytic degradation shows the absence of some amino acids at the C-end of protein and is electrophoretically homogeneous, while its antiviral, antiproliferative and immunomodulating effects are less pronounced than those of gamma interferon with a molecular weight of 18 KD.
Subject(s)
Interferon-gamma/drug effects , Peptide Hydrolases/pharmacology , Animals , Cells, Cultured/drug effects , Drug Evaluation, Preclinical , Encephalomyocarditis virus/drug effects , Escherichia coli , Humans , Interferon-gamma/pharmacology , Mice , Molecular Weight , Recombinant Proteins , Structure-Activity Relationship , Tumor Cells, Cultured/drug effects , Vesicular stomatitis Indiana virus/drug effectsABSTRACT
A single-step procedure is described for isolation of alpha 1-inhibitor of proteases (alpha 1-IP) from human blood plasma using affinity chromatography on immunosorbent containing monoclonal antibodies against alpha 1-IP. Activity of the alpha 1-IP preparation, estimated by means of specific trypsin inhibition, was increased 61.1-fold after the chromatography, with a yield of the end product 20%. The preparation of alpha 1-IP obtained exhibited electrophoretic and immunochemical homogeneity.
