Genomic diversity of the genus Stenotrophomonas

The clinical and environmental importance of Stenotrophomonas bacteria requires thorough, molecular studies on their epidemiology and taxonomy. In order to obtain a complete genomic profile of this genus, over 100 Stenotrophomonas maltophilia strains from various origins were investigated by AFLP fingerprinting. A subset of these strains was analysed by DNA hybridization and 16S rDNA sequencing. In contrast to their high phenotypic homogeneity, the strains were found to be very heterogeneous genotypically by AFLP fingerprinting. Nevertheless, ten cores of highly similar strains representing ten genomic groups were observed. The same groups could be retrieved by DNA hybridizations and also, partly, by 16S rDNA sequence analysis. The intergroup DNA similarities were too high to create confident species delineations, neither could the genomic groups be characterized by phenotypic features.