ABSTRACT
Plasmids with the molecular weights of 1.6 to 21.0 MD were detected in Staphylococcus aureus. The plasmids determined resistance to benzylpenicillin, ampicillin, streptomycin, erythromycin, tetracycline, chloramphenicol, arsenate and arsenite. Strain p16 of Staphylococcus aureus contained plasmid pL16 with the molecular weight of 18.0 MD determining resistance to erythromycin, streptomycin, benzylpenicillin and ampicillin. The plasmid has two replication sites and is likely a natural recombinant of two plasmids.
Subject(s)
Plasmids/genetics , Staphylococcus aureus/genetics , Drug Resistance, Microbial/genetics , Molecular Weight , R Factors/genetics , Transformation, GeneticABSTRACT
The molecular organization of the alpha-hemolysin gene from Staphylococcus aureus strain O15 has been studied. Hybridization of the DNA from this strain with the [32P]-labeled cloned fragment containing alpha-hemolysin gene has shown the studied gene to be unique in the genome of the strain. Sequences homologous to the gene were not found to be dispersed along the genome of Staphylococcus aureus O15. The presence of alpha-hemolysin gene in some Staphylococcus epidermidis strains has been monitored. The strains 1413, 303 have been demonstrated to contain no gene for alpha-hemolysin. The hemolysin genes were found in the genomes of the strains 159, 169, 180 by DNA hybridization technique. In the genome of the strain 180 the long region including the right end of alpha-hemolysin gene is deleted. Hybridization with the net RNA of these strains shows the absence of transcription of intact as well as deleted alpha-hemolysin genes.
Subject(s)
Genes, Bacterial , Hemolysin Factors/genetics , Hemolysin Proteins/genetics , Plasmids/genetics , Staphylococcus epidermidis/genetics , Transcription, Genetic , Cloning, Molecular , DNA, Bacterial/genetics , Nucleic Acid Hybridization , Sequence Homology, Nucleic AcidABSTRACT
The genomic library of Staphylococcus aureus O15 has been constructed on the EMBL-3 vector. The synthetic oligonucleotide probes to N- and C-end regions of alpha-hemolysin permitted identification of the recombinant bacteriophage clone RS-1 containing a gene for this protein. The restriction map of the cloned fragment has been constructed for restriction endonucleases SalGI, EcoRV, PstI, PvuII. Expression of the alpha-hemolysin gene in phagolysate of the recombinant clone RS-1 (1000 units per ml) has been demonstrated.
Subject(s)
Cloning, Molecular , Genes, Bacterial , Hemolysin Proteins/genetics , Staphylococcus aureus/genetics , Base Sequence , DNA Probes , Genetic Vectors , Molecular Sequence Data , Restriction Mapping , Staphylococcus Phages/geneticsSubject(s)
DNA Restriction Enzymes/pharmacology , DNA, Viral/genetics , Staphylococcus Phages/genetics , Staphylococcus aureus/enzymology , Base Sequence/drug effects , Binding Sites/drug effects , DNA, Viral/drug effects , DNA, Viral/metabolism , Staphylococcus Phages/drug effects , Staphylococcus Phages/pathogenicity , Virulence/drug effects , Virus ReplicationABSTRACT
Equilibrium centrifugation, spectral analysis of thermal denaturation and direct chemical determinations showed staphylococcal phage Sb-I DNA to be characterized by a standard set of nitric bases (28.5 mol.2./% G-C). No abnormal bases or other extracomponents were found. From the differential spectral analysis of melting interval it is concluded that G-C pairs are distributed along DNA molecule in a Gauss type. Spectrophotometric and thermodynamic parameters of melting show phage Sv-I DNA to have a typical double-stranded structure. DNA is characterized by enthalpies of conformational transitions of spiral=glome delta H=11.4 cal/g and delta H = 9.7 cal/g for 1 x SSC and 0.1 x SSC diluents, respectively.
Subject(s)
DNA, Viral , Nucleic Acid Conformation , Staphylococcus Phages/analysis , Centrifugation, Density Gradient , Chemical Phenomena , Chemistry, Physical , Hot Temperature , Nucleic Acid Denaturation , Spectrum Analysis , ThermodynamicsABSTRACT
Virions of polyvalent staphylococcal bacteriophage SB-I have an octaedric head (800 X 700 A) and a long contractive process (1800 X 150 A). The phage particle with a molecular weight of 150 X 10(6) daltons contains 48% double-stranded RNA and 52% protein. The proteinic component of the phage consists of 18 heterogeneic polypeptide chains.
Subject(s)
DNA, Viral/analysis , Staphylococcus Phages/analysis , Viral Proteins/analysis , Virion/analysis , Centrifugation, Density Gradient , Densitometry , Microscopy, Electron , Staphylococcus Phages/ultrastructure , Virion/ultrastructureABSTRACT
The molecular weight of phage FI-1 DNA is determined by the methods of sedimentation and kinetics of reassociation, as well as from buoyant density values of virion components and specific partial volume of DNA (85X10(6) daltons). The spectral analyses showed that the distribution of guanine-cytosine pairs along the whole length of the molecule is Gaussian. The DNA content in the particle of FI-1 makes up to 41%, which is 7% less as compared to the morphologically related phage T4. The protein component analysis of phage FI-1 demonstrated that the genome of this virus is capable to encode at least 20 different proteins. Possible reasons for differences in the molecular weights of the genomes of T4 and FI-1 phages are discussed.
Subject(s)
Coliphages/analysis , DNA, Viral , Chemical Phenomena , Chemistry , Electrophoresis, Polyacrylamide Gel , Hot Temperature , Molecular Weight , Nucleotides , Spectrum Analysis , Viral Proteins/analysisABSTRACT
The composition of nitrous bases of phage FI-1 DNA was studied. As is evidenced from the values of buoyant density in CsCl (p=1,7093 g/cm(3)), melting temperature (T degrees m=86,05 degrees), spectral parameters and direct chromatographic determination, the DNA analysed contains 41,5 mole% pairs of guanine-cystosine. 5-hydroxymethylcytosine and other anomalous bases were not found. Chemical identification and jaxtposition of data of buoyant density in CsCl and Cs2SO4 (p=1,4466 g/cm(3)) and T degrees m. showed the presence of the extra-sugar component in DNA, most likely in the form of hentibiose. Spectral character of thermal denaturation of DNA in different solvents is indicative of the double helixity of its structure. DNA is characterized by enthalpies of conformational transitions "helix coil" (deltaH=12,3 kcal/g) and (deltaH=10 kcal/g) for the solvents, 1 x SSC, and 0,1 x SSC, correspondingly. The presence of extra-sugar in DNA with standard set of nitrous bases is discussed.
Subject(s)
Coliphages/analysis , DNA, Viral , Carbohydrates/analysis , Chemical Phenomena , Chemistry , Deoxyribonucleotides/analysis , Nucleic Acid Conformation , Nucleic Acid Denaturation , ThermodynamicsABSTRACT
Physico-chemical parameters and features of macromolecular orgnization of FI-5 phage were studied. This virus was shown to contain a molecule of double-strander DNA with the standard set of nitrous bases (37.8 mol% GC). The molecule of this DNA in situ is characterized by partial disorder of the second structure. Phage virions contain about 47% of DNA and 53% of protein. The genome of the phage is represented by a DNA molecule with molecular weight 65X10(6) daltons and is capable of coding for a least 15 different proteins.
