RESUMO
Intensity of luminescence quenching in recombinant strains of Escherichia coli with cloned lux-operones by human blood serum is directly proportional to the degree of bactericidal effect assessed by nephelometric and bacteriological methods. This correlation was most characteristic of E. coli with luminescence genes from Photobacterium leiognathi, which substantiates its use in the development of the kinetic bioluminescent method to determine of serum bactericidal activity. The possibility of using this method for evaluation of activity of classic and alternative pathways of compliment activation was demonstrated by using zymosan or EGTA-Mg(2+)-treated sera and C1-C5-deficient sera.
Assuntos
Atividade Bactericida do Sangue/fisiologia , Ativação do Complemento/fisiologia , Escherichia coli/fisiologia , Escherichia coli/genética , Humanos , Cinética , Medições Luminescentes , Proteínas Luminescentes/genética , Nefelometria e Turbidimetria , Photobacterium/genética , Photorhabdus/genética , ZimosanRESUMO
Biphasic modification of bacterial bioluminescence by human serum was revealed: bioluminescence was inhibited at high concentrations of the serum and stimulated at low concentrations. Effects of temperature and duration of exposure on bioluminescence manifested in stimulation of the inhibitory effect at higher temperature and longer exposure. The degree of inhibition of bioluminescence under in the presence of serum depends on species characteristics of the microorganism and nature of the luminescent system.
