RESUMO
Streptococcus pneumoniae is among the most significant causes of bacterial disease in humans. Here we report the 2,038,615-bp genomic sequence of the gram-positive bacterium S. pneumoniae R6. Because the R6 strain is avirulent and, more importantly, because it is readily transformed with DNA from homologous species and many heterologous species, it is the principal platform for investigation of the biology of this important pathogen. It is also used as a primary vehicle for genomics-based development of antibiotics for gram-positive bacteria. In our analysis of the genome, we identified a large number of new uncharacterized genes predicted to encode proteins that either reside on the surface of the cell or are secreted. Among those proteins there may be new targets for vaccine and antibiotic development.
Assuntos
Genoma Bacteriano , Análise de Sequência de DNA , Streptococcus pneumoniae/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Elementos de DNA Transponíveis/genética , Humanos , Dados de Sequência MolecularRESUMO
A fiberoptic spectrofluorimeter was constructed capable of remote operation of up to 18 biosensors under fully automated, multiplexed control. Excitation and emission wavelengths were separately adjustable, as were optical bandwidths, signal gain, phase, integration time, and illumination duty cycle. Synchronous demodulation was used to enhance signal-to-noise ratio and allow operation under ambient lighting conditions. Detection limit for aqueous sodium-fluorescein was below 1 ng/mL at greater than unity signal-to-noise ratio, with effective sampling volumes less than 0.02 microL. The fluorimeter showed characteristics fiberoptic sampling behavior with asymptotic nonzero signal magnitudes under increasing pathlength conditions.