RESUMEN
Two identical isolates were recovered in pure culture from the blood and urine of a patient suffering from severe septicaemia associated with obstructive pyelonephritis secondary to lithotripsy. Preliminary phenotypic and genotypic characterizations based on serological, biochemical and sequence analyses following PCR amplification of selected gene regions indicate that this organism represents a potential new Francisella genomic species.
Asunto(s)
Bacteriemia/microbiología , Sangre/microbiología , Francisella/genética , Francisella/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/microbiología , Orina/microbiología , Adulto , Técnicas de Tipificación Bacteriana , ADN Bacteriano/análisis , ADN Bacteriano/genética , Electroforesis en Gel de Poliacrilamida , Francisella/clasificación , Genes de ARNr , Humanos , Secuencias Repetitivas Esparcidas/genética , Litotricia/efectos adversos , Masculino , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple , Pielonefritis/etiología , ARN Ribosómico 16S/genética , Alineación de SecuenciaAsunto(s)
Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Síndrome de la Serotonina/diagnóstico , Sertralina/efectos adversos , Compresión de la Médula Espinal/diagnóstico , Anciano , Anciano de 80 o más Años , Depresión/tratamiento farmacológico , Diagnóstico Diferencial , Humanos , Masculino , Neoplasias de la Próstata/psicología , Síndrome de la Serotonina/inducido químicamente , Neoplasias de la Columna Vertebral/secundarioRESUMEN
We describe an immunocompetent adolescent who presented with exceptionally severe Bordetella holmesii infection, including previously undescribed manifestations. Sequelae included a severe restrictive lung defect due to pulmonary fibrosis.
Asunto(s)
Infecciones por Bordetella/diagnóstico , Bordetella/aislamiento & purificación , Genes de ARNr , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Adolescente , Bordetella/clasificación , Bordetella/genética , Infecciones por Bordetella/microbiología , Femenino , Genes Bacterianos , Humanos , Inmunocompetencia , Datos de Secuencia MolecularRESUMEN
In Escherichia coli K-12, the shiA gene is involved in the uptake of shikimate. This gene has been cloned and its nucleotide sequence determined. The gene is predicted to encode a protein of 438 amino acids and lies adjacent to the amn gene. The hydropathy profile and the amino acid sequence indicate that the ShiA protein is a polytopic membrane protein that shows a homology with members of the major facilitator superfamily of transport proteins. Recombining an inactive form of the cloned gene into the chromosome creates mutants unable to transport shikimate. Introducing a wild-type gene on a multicopy plasmid into a shiA mutant restores the ability to transport shikimate. When this multicopy shiA plasmid is introduced into an aroE strain, this strain is now able to grow with shikimate as the aromatic supplement, consistent with the notion that dehydroshikimate (DHS) accumulated in an aroE strain prevents uptake of shikimate by competition. Expression of the shiA gene does not appear to be regulated by the TyrR protein, a repressor/activator that controls the expression of other genes involved with the biosynthesis or transport of the aromatic amino acids.
Asunto(s)
Proteínas Bacterianas/biosíntesis , Proteínas Portadoras/biosíntesis , Proteínas de Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Transporte de Membrana , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Portadoras/química , Proteínas Portadoras/genética , Mapeo Cromosómico , Clonación Molecular , Genes Bacterianos , Modelos Moleculares , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Estructura Secundaria de Proteína , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Ácido Shikímico/metabolismoRESUMEN
In the course of sequencing the aroK gene, a number of errors were found in the published sequence. The corrected sequence alters the length of the aroK coding region such that the AroK and AroL proteins are now of comparable length and the homology between them extends the entire length of the two enzymes.
Asunto(s)
Escherichia coli/genética , Isoenzimas/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Escherichia coli/enzimología , Datos de Secuencia Molecular , Mutagénesis , Biosíntesis de Proteínas , Sistemas de Lectura/genética , Proteínas Recombinantes de Fusión/biosíntesis , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Ácido Shikímico/metabolismoRESUMEN
pheV, one of the genes that code for tRNA(Phe), was deleted from the chromosome of a strain of Escherichia coli K-12. As a consequence of this mutation, expression of pheA, the gene for chorismate mutase P-prephenate dehydratase, the first enzyme in the terminal pathway of phenylalanine biosynthesis, was derepressed. Similar derepression of pheA has been reported in pheR mutants of E. coli K-12 (J. Gowrishankar and J. Pittard, J. Bacteriol. 150:1130-1137, 1982). Attempts to introduce a pheR mutation into the delta pheV strain failed under circumstances suggesting that this combination of mutations is lethal. Southern blot analysis of pheV+ and delta pheV strains indicated that there are only two tRNA(Phe) genes in E. coli. It is recommended that the names pheU and pheV be retained for these genes.
Asunto(s)
Escherichia coli/genética , Genes Bacterianos , Familia de Multigenes , ARN de Transferencia de Fenilalanina/genética , Southern Blotting , Deleción Cromosómica , Cromosomas Bacterianos , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Genotipo , Hibridación de Ácido Nucleico , Mapeo RestrictivoRESUMEN
Two cases of squamous cell carcinoma complicating longstanding acne conglobata in a father and daughter are described. The outcome was fatal in both cases.
Asunto(s)
Acné Vulgar/genética , Carcinoma de Células Escamosas/genética , Neoplasias Cutáneas/genética , Acné Vulgar/complicaciones , Acné Vulgar/patología , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/patologíaRESUMEN
A mutant strain of Escherichia coli K-12 that is defective in both the tyrosine-specific and phenylalanine-specific transport systems was isolated. The defects in these systems were shown to be due to mutations in two distinct loci, tyrP and pheP, respectively.
Asunto(s)
Escherichia coli/metabolismo , Genes , Fenilalanina/metabolismo , Tirosina/metabolismo , Transporte Biológico Activo , Mapeo Cromosómico , Cromosomas Bacterianos , Escherichia coli/genética , MutaciónRESUMEN
The regulation of the aromatic amino acid transport systems was investigated. The common (general) aromatic transport system and the tyrosine-specific transport system were found to be subject to repression control, thus confirming earlier reports. In addition, tryosine- and tryptophan-specific transport were found to be enhanced by growth of cells with phenylalanine. The repression and enhancement of the transport systems was abolished in a strain carrying an amber mutation in the regulator gene tyrR. This indicates that the tyrR gene product, which was previously shown to be involved in regulation of aromatic biosynthetic enzymes, is also involved in the regulation of the aromatic amino acid transport systems.