RESUMEN
Botulism is a severe neuroparalytic disorder that can be potentially life-threatening. In Barcelona, Spain, no outbreaks had been reported in the past 25 years. However, in September 2011, two outbreaks occurred involving two different families. A rare case of Clostridium baratii which produced a neurotoxin F outbreak was detected in five family members who had shared lunch, and several days before that another family was affected by C. botulinum toxin A which was probably present in homemade pâté.
Asunto(s)
Botulismo/epidemiología , Clostridium/clasificación , Clostridium/aislamiento & purificación , Brotes de Enfermedades , Toxinas Botulínicas/análisis , Salud de la Familia , Femenino , Humanos , Masculino , España/epidemiologíaRESUMEN
A procedure has been developed whereby the components of the nitrate reductase complex from the membrane of Escherichia coli can be extracted by means of a nonionic detergent and separated from each other as discrete elements in an active form. It is not yet clear whether these are the dissociated enzymatic elements or whether they are fragments containing other membrane proteins. In any case, they appeared nearly lipid-free and still active.
Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Escherichia coli/enzimología , Oxidorreductasas/aislamiento & purificación , Anaerobiosis , Membrana Celular/enzimología , Cromatografía en Gel , Medios de Cultivo , Citocromos/aislamiento & purificación , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Formiatos , Isótopos de Hierro , Lípidos/aislamiento & purificación , Métodos , Nitratos/metabolismo , Fosfolípidos/aislamiento & purificación , Solventes , Espectrofotometría , TensoactivosRESUMEN
The mediated transport of citrate in Aerobacter aerogenes was studied. According to data obtained by examining the distribution of radioactive citrate at room temperature and at 0 C, a carrier system appears to be located on the membrane. The carrier system is inducible and very specific, not acting on the related compounds isocitrate and cis-aconitate. Induction required synthesis of both ribonucleic acid and protein as determined by starving auxotrophic mutants and by using specific inhibitors of protein synthesis. Citrate transport was inhibited by N-ethyl maleimide, dinitrofluorobenzene, and uranyl nitrate. A kinetic study of uranyl nitrate inhibition revealed that the inhibition of citrate transport was different from that of glucose penetration. Cyanide also discriminated citrate from glucose penetration inhibiting only the former. These last results suggested that energy is required for citrate penetration.