RESUMEN
Bacteria capable of hexavalent chromium (Cr6+) reduction can be found in Cr6+-containing sewage and sediments of purification tanks of industrial plants. They cannot be detected in water and soil samples containing no chromium compounds. Bacteria reducing chromium belong to the genera Aeromonas, Escherichia, Pseudomonas and Enterobacter. Their activity of Cr6+ reduction correlates with the high resistance to the elevated content of this ion in the medium. The fine cell structure of these bacteria is described.
Asunto(s)
Bacterias/análisis , Cromo/metabolismo , Aguas del Alcantarillado/análisis , Aeromonas/análisis , Enterobacter/análisis , Escherichia/análisis , Oxidación-Reducción , Pseudomonas/análisisRESUMEN
The comparative study of the fatty acid composition of bacterial lipopolysaccharides (LPS) in the genera Escherichia, Shigella, Salmonella has been carried out under identical experimental conditions. The LPS of the bacteria under study have been found to contain a number of saturated fatty acids and oxyacids which could not be previously detected in these bacteria in other studies. In all bacterial strains under study LPS include mainly 3-oxytetradecanoic, tetradecanoic and dodecanoic fatty acids. The essential feature of the fatty acid composition of Salmonella is the presence of 2-oxytetradecanoic acid; this acid is absent in Escherichia and Shigella, which can thus be used as a differentiating criterion. The content of other fatty acids in Salmonella is similar to that in Escherichia and Shigella. These data confirm that the genera Escherichia, Shigella and Salmonella are phylogenetically related, the relationship between Escherichia and Shigella being more close.
Asunto(s)
Escherichia/clasificación , Ácidos Grasos/análisis , Lipopolisacáridos/análisis , Salmonella/clasificación , Shigella/clasificación , Cromatografía de Gases , Escherichia/análisis , Ácidos Grasos/clasificación , Lipopolisacáridos/clasificación , Salmonella/análisis , Shigella/análisisAsunto(s)
Antígenos Bacterianos/análisis , Endotoxinas/análisis , Lipopolisacáridos/análisis , Antígenos Bacterianos/inmunología , Pared Celular/análisis , Pared Celular/inmunología , Fenómenos Químicos , Química , Endotoxinas/inmunología , Escherichia/análisis , Escherichia/inmunología , Lípido A/análisis , Lipopolisacáridos/síntesis química , Lipopolisacáridos/inmunología , Antígenos O , Factores R , Salmonella/análisis , Salmonella/inmunologíaRESUMEN
The thermal denaturation spectra of E. coli 50s and 30s ribosomal sub units and of their isolated RNA's were studied over the wavelength range of 2300-3000 Angstrom. It was possible to fit the experimental denaturation spectra with super positions of the reference spectra for denaturation of A - U and G - C base pairs derived from model polyribonucleotides. The coefficients of these linear combinations were used to calculate the fractions of A - U and G - C base pairs in the samples. It was found that the helical content of the RNA's inside the subunits is smaller than that of the isolated RNA's, thus suggesting that proteins may affect the secondary structure of RNA in the ribosome.
Asunto(s)
Escherichia/análisis , ARN Bacteriano , ARN Ribosómico , Ribosomas/análisis , Escherichia coli/ultraestructura , Magnesio , Conformación de Ácido Nucleico , Desnaturalización de Ácido Nucleico , ARN Bacteriano/análisis , ARN Ribosómico/análisis , Ribosomas/ultraestructura , Espectrofotometría Ultravioleta , TemperaturaAsunto(s)
Escherichia coli/ultraestructura , ARN Bacteriano , ARN Ribosómico/análisis , ARN de Transferencia , Ribosomas/ultraestructura , Aldehídos , Fosfatasa Alcalina , Secuencia de Bases , Sitios de Unión , Electroforesis en Papel , Escherichia/análisis , Oligonucleótidos/análisis , ARN Bacteriano/análisis , ARN de Transferencia/análisis , Ribonucleasas , Ribosomas/análisisAsunto(s)
Proteínas Bacterianas/análisis , Enterobacteriaceae/análisis , Ribosomas/análisis , Electroforesis en Gel de Poliacrilamida , Enterobacter/análisis , Erwinia/análisis , Escherichia/análisis , Escherichia coli/análisis , Técnicas Inmunológicas , Peso Molecular , Proteus vulgaris/análisis , Salmonella typhimurium/análisis , Serratia marcescens/análisis , Shigella/análisisRESUMEN
Polynucleotide sequence relatedness studies were carried out to determine the extent of divergence present in members of the tribe Salmonelleae and between salmonellae and other enteric bacteria. Typical Salmonella were 85 to 100% related. Two groups of biochemically atypical Salmonella showed somewhat lower binding to typical salmonellae and to each other. Arizona were 70 to 80% related to salmonellae. Two groups of Arizona were detected. These groups correlated with the presence of monophasic or diphasic flagellar antigens. Salmonella and Arizona were no more related to Citrobacter than to Escherichia coli (45-55%). Relatedness of Salmonella and Arizona to other enterobacteria ranged from 20 to 40% with klebsiellae and shigellae, to 20 to 25% with erwiniae, and to less than 20% with edwardsiellae and Proteus mirabilis.
Asunto(s)
ADN Bacteriano/análisis , Salmonella/análisis , Secuencia de Bases , Evolución Biológica , Cromatografía , ADN Bacteriano/aislamiento & purificación , ADN de Cadena Simple/aislamiento & purificación , Enterobacteriaceae/análisis , Enterobacteriaceae/clasificación , Escherichia/análisis , Escherichia/clasificación , Calor , Hidroxiapatitas , Peso Molecular , Desnaturalización de Ácido Nucleico , Hibridación de Ácido Nucleico , Isótopos de Fósforo , Polinucleótidos/análisis , Salmonella/clasificación , Especificidad de la Especie , EspectrofotometríaRESUMEN
The fatty acid compositions of stationary-phase cultures of Arizona arizonae, Citrobacter freundii, Providencia alcalifaciens, Providencia stuartii, and Providencia sp. were studied. The major fatty acids of A. arizonae, C. freundii, and Providencia were 16:0, 16:1, 17:cyclopropane, and 19:cyclopropane. The fatty acid compositions of the two strains of A. arizonae examined were similar to each other, but the three strains of C. freundii differed from one another in their fatty acid compositions. In both A. arizonae and C. freundii, the relative quantities of saturated, unsaturated, and cyclopropane fatty acids were similar to those which have been found in stationary-phase cultures of other members of the Enterobacteriaceae. The three strains of Providencia also differed from one another in their fatty acid compositions. In all three strains, the total quantity of unsaturated fatty acids was larger and that of the cyclopropane fatty acids was smaller than those found in stationary-phase cultures of other enteric bacteria.
Asunto(s)
Enterobacteriaceae/análisis , Escherichia/análisis , Ácidos Grasos/análisis , Proteus/análisis , Cromatografía de Gases , Ciclopropanos/análisis , Ácidos Grasos Insaturados/análisisAsunto(s)
Escherichia/análisis , Pruebas de Aglutinación , Bacterias/análisis , Fenómenos Bioquímicos , Bioquímica , Pruebas Enzimáticas Clínicas , Medios de Cultivo , Cianuros , Escherichia/enzimología , Escherichia/inmunología , Escherichia/aislamiento & purificación , Sueros Inmunes , Lisina , Potasio , Salmonella/análisisAsunto(s)
Membrana Celular/análisis , Pared Celular/análisis , Colicinas/farmacología , Escherichia/análisis , Mutación , Resistencia a las Penicilinas , Ampicilina/farmacología , Proteínas Bacterianas/análisis , Bacteriocinas/biosíntesis , Bacteriocinas/farmacología , Centrifugación por Gradiente de Densidad , Ácidos Cólicos/farmacología , Cromatografía en Capa Delgada , Densitometría , Ácido Edético/farmacología , Electroforesis en Gel de Poliacrilamida , Escherichia/clasificación , Escherichia/citología , Escherichia/efectos de los fármacos , Klebsiella pneumoniae/metabolismo , Fosfolípidos/análisisAsunto(s)
Escherichia/análisis , Péptidos/análisis , Ribosomas/análisis , Fenómenos Químicos , Química , Cromatografía , Farmacorresistencia Microbiana , Eritromicina , Escherichia/efectos de los fármacos , Escherichia coli/análisis , Escherichia coli/efectos de los fármacos , Especificidad de la EspecieRESUMEN
Compositions of the ribosomal proteins of 60 bacterial strains belonging to the genus Escherichia and its related genera were examined by use of a column of carboxymethyl cellulose. The ribosomes were classified into seven groups and were further differentiated into several types (subgroups) according to their protein compositions. It was shown that ribosomal protein composition is a useful characteristic for studies of bacterial taxonomy.
Asunto(s)
Proteínas Bacterianas/análisis , Escherichia/clasificación , Ribosomas/análisis , Isótopos de Carbono , Centrifugación por Gradiente de Densidad , Cromatografía , Enterobacteriaceae/análisis , Escherichia/análisis , Lisina , Métodos , Metilcelulosa , Proteus/análisis , Salmonella/análisis , Shigella/análisis , Especificidad de la Especie , SacarosaAsunto(s)
Escherichia/análisis , ARN Bacteriano/análisis , Acrilatos , Isótopos de Carbono , Electroforesis , Geles , Glicósido Hidrolasas , Ribosomas/análisis , Tritio , UraciloRESUMEN
Phenol-soluble lipopolysaccharides were obtained from the interphase and phenol phase fractions of 44% aqueous phenol-extracted Citrobacter species. Upon detailed investigation of C. freundii 8090, the two lipopolysaccharide fractions were found to contain different amounts of lipid A, although qualitative composition was similar. Both contained lipid A, 2-keto-deoxyoctonic acid, heptose, phosphate, d-glucose, galactose, rhamnose, 2-acetamido-2 deoxy-d-glucose, 3-acetamido-3,6-dideoxy-d-glucose, O-acetyl, and trace amino acids. Partially purified phenol-phase lipopolysaccharide partitioned into the phenol-soluble phase when refractionated with 44% aqueous phenol, and was further found to be soluble in 88% phenol, 95% ethyl alcohol, and chloroform-methanol (2:1).