An online scheme to assign Stenotrophomonas isolates to genomic groups was developed using the multilocus sequence analysis (MLSA), which is based on the DNA sequencing of selected fragments of the housekeeping genes ATP synthase alpha subunit (atpA), the recombination repair protein (recA), the RNA polymerase alpha subunit (rpoA) and the excision repair beta subunit (uvrB). This MLSA-based scheme was validated using eight of the 10 Stenotrophomonas species that have been previously described. The environmental and nosocomial Stenotrophomonas strains were characterised using MLSA, 16S rRNA sequencing and DNA-DNA hybridisation (DDH) analyses. Strains of the same species were found to have greater than 95% concatenated sequence similarity and specific strains formed cohesive readily recognisable phylogenetic groups. Therefore, MLSA appeared to be an effective alternative methodology to amplified fragment length polymorphism fingerprint and DDH techniques. Strains of Stenotrophomonas can be readily assigned through the open database resource that was developed in the current study (www.steno.lncc.br/).

O estudo da cinética de crescimento de Acetivibrio cellulolyticus cultivado em três diferentes substratos celulósicos (celulose amorfa, celulose cristalina e celobiose) revelou que em celobiose, a velocidade específica de crescimento foi maior que nos dois tipos de celulose. A atividade de endoglicanase foi maior em celulose amorfa; em celulose cristalina a atividade enzimática, aumentou durante a fase estacionária.

The growth kinetics of Acetivibrio cellulolyticus grown in medium containing different carbon sources (cellobiose, amorphous or crystalline cellulose) was investigated. The specific growth rate was higher in cellobiose fed cultures than in the presence of the other two substrates. Endoglucanase production was greater in cultures grown on amorphous cellulose; enzyme activity increased during the stationary phase in cultures grown on crystalline cellulose.