Prokaryotic taxonomy and phylogeny in the genomic era: advancements and challenges ahead.

Advancing prokaryotic taxonomy constitutes a contemporary academic challenge as well as practical necessity. Genome sequencing has greatly facilitated the evaluation of the current taxonomic system and the development of simpler, more portable and accurate, sequence-based alternatives to substitute for the traditional cumbersome methods. Studies based on the former genome-enabled methods reveal that existing taxonomic designations, including the species level, correspond frequently to a continuum of genetic diversity as opposed to natural groupings (e.g. biological species). Improving such artificial and often ambiguous taxonomic designations, however, will require larger genomic datasets and more carefully designed sampling of natural populations. Only then can the promise for a superior genome-based taxonomy materialize.