ABSTRACT
The genomic library of Staphylococcus aureus genes on the plasmid vector pSL5 has been constructed. The library contains a 2.5 kb HindIII DNA fragment including the gene for enterotoxin A. The entA gene on the high copy number plasmids in the Escherichia coli cells deficient in proteolysis determines the synthesis of enterotoxin A in the amounts comparable to the ones in the parent strain Staphylococcus aureus FRI 722(H).
Subject(s)
Enterotoxins/genetics , Gene Expression Regulation, Bacterial , Genes, Bacterial , Staphylococcus aureus/genetics , Bacillus subtilis/genetics , Escherichia coli/genetics , Gene Library , Plasmids , Restriction MappingABSTRACT
Gene ent-A has been cloned on phage vector pSL5 with the use of the gene library of S. aureus FR1722(H). It is located within DNA fragment Hind III having 2,500 nucleotide pairs.
Subject(s)
Cloning, Molecular/methods , Enterotoxins/genetics , Escherichia coli/genetics , Gene Expression Regulation, Bacterial/genetics , Genes, Bacterial , Staphylococcus aureus/genetics , Coliphages/genetics , DNA, Bacterial/genetics , Gene Library , Genetic Vectors/genetics , Plasmids/genetics , Staphylococcus Phages/genetics , Transfection/geneticsABSTRACT
A rat isolated heart was used to demonstrate a protective effect of phosphocreatine (10 mM) in total normothermic ischemia (25 min) with subsequent reperfusion with the Krebs-Henzeleit solution and in cardioplegia in the St Thomas Hospital solution. The effect consisted in reduction in ischemic and reperfusion contraction and a 2-3-fold increase in cardiac output as compared with the control. A 20 per cent increase in the calcium content in the solution did not influence the phosphocreatine effect. Application of tocopheryl phosphate (0.1 microM) had no effect on the ischemic contraction but reduced diastolic pressure on reperfusion and provided a better maintenance of the cardiac parameters. The tocopheryl phosphate action increased when used in combination with phosphocreatine. The findings show that phosphocreatine slows down the development of ischemic damage and onset of irreversibility while antioxidants exert a protective effect by preventing a reperfusion damage to the heart.
Subject(s)
Cell Communication/physiology , Second Messenger Systems/physiology , Animals , Cell Division/physiology , Culture Media , Cyclic AMP/physiology , Enterotoxins/physiology , Fibroblasts/cytology , Fibroblasts/physiology , Growth Substances/physiology , Humans , In Vitro Techniques , Mice , Mitogens/pharmacology , Protein Kinases/physiologyABSTRACT
Recent studies on the mechanisms of cell regulation have demonstrated that the reactions occurring with participation of secondary messengers, i.e., cyclic adenosine-3',5'-monophosphate (cAMP), Ca2+, 2',5'-oligoadenylate (oligoA), etc., are closely interrelated and the secondary messengers involved therein can thus be regarded as components of the integral regulatory system of the cell. The interaction between these components occurs via at least two pathways. Firstly, some reactions, that are vital for the cell, are under a simultaneous control of several messengers. Secondly, any changes in the intracellular level of one of the messengers inevitably affects the concentrations of other messengers.
Subject(s)
Cyclic AMP/physiology , Adenine Nucleotides/metabolism , Animals , Calcium/physiology , Cell Line , Mice , Oligoribonucleotides/metabolism , Protein Synthesis Inhibitors , Second Messenger SystemsABSTRACT
Two procedures for isolation of homogeneous beta 2-microglobulin from urine of patients with systemic lupus erythematosus were developed: a procedure for isolation of beta 2-microglobulin with two-stage gel chromatography on Sephacryl S-200 and a procedure for isolation of homogeneous beta 2-microglobulin with affinity chromatography on rabbit polyclonal antibodies. The microglobulins isolated with the two procedures showed identical physicochemical properties and were used in development of a competitive immunoenzymatic assay method for determination of beta 2-microglobulin in the blood. The method was approved for determination of beta 2-microglobulin in blood serum of patients.
Subject(s)
beta 2-Microglobulin/isolation & purification , Animals , Antibodies/isolation & purification , Antibody Affinity , Chromatography, Gel , Chromatography, High Pressure Liquid , Humans , Immunization , Immunoenzyme Techniques , Isoelectric Focusing , Lupus Erythematosus, Systemic/blood , Molecular Weight , Rabbits , beta 2-Microglobulin/analysis , beta 2-Microglobulin/immunologySubject(s)
Colloids , Micelles , Polymers , Proteins , Surface-Active Agents , Dioctyl Sulfosuccinic AcidABSTRACT
The effect of nerve growth factor (NGF), purified to homogeneity from bovine seminal plasma using HPLC, on the level of endogenous ADP-ribosylation in pheochromocytoma PC-12 cell line was studied. NGF caused a 30% inhibition of ADP-ribosylation in the cellular homogenate, a 25% inhibition during serum-free cultivation, and a 50% inhibition in the presence of serum in the culture medium. NGF inhibited ADP-ribosylation of several proteins, including a protein with molecular weight of 40,000, probably of membrane origin. A possibility of the interrelation between NGF and cyclase system via receptor-dependent ADP-ribosylation of regulatory components of the adenylate cyclase was discussed.
Subject(s)
Adenosine Diphosphate Ribose/metabolism , Nerve Growth Factors/pharmacology , Pheochromocytoma/metabolism , Cell Line , Depression, Chemical , Electrophoresis, Polyacrylamide Gel , HumansSubject(s)
Peptide Hydrolases , Peptides/isolation & purification , Protease Inhibitors/isolation & purification , Streptomyces/metabolism , Amylases/antagonists & inhibitors , Drug Combinations/antagonists & inhibitors , Molecular Weight , Papain/antagonists & inhibitors , Peptides/analysis , Protease Inhibitors/analysis , Trypsin Inhibitors/analysis , Trypsin Inhibitors/isolation & purificationSubject(s)
2',3'-Cyclic-Nucleotide Phosphodiesterases/metabolism , Bacterial Proteins/pharmacology , Calmodulin/metabolism , Phosphoric Diester Hydrolases/metabolism , Staphylococcus aureus/metabolism , Amino Acids/analysis , Bacterial Proteins/analysis , Brain/enzymology , Brain Chemistry , Calmodulin/analysis , Enzyme Activation/drug effects , Humans , In Vitro TechniquesABSTRACT
The primary structure of calmodulin from human brain has been determined. As compared to calmodulin from bovine brain, it shows three substitutions of the amide----acid type at positions 24, 60, 129, and two acid----amide changes at positions 104 and 135.
