Ribosomal RNA phylogenies for the vibrio-enteric group of eubacteria.

Comparisons between the ribonucleotide sequences of 5S rRNAs of the Gram-negative eubacteria indicate that several families, namely Enterobacteriaceae, Vibrionaceae and Aeromonadaceae possess remarkably similar evolutionary histories. A study of the phylogenetic relationships among these groups, through cluster analysis and construction of evolutionary trees, suggests the existence of dissimilar rates of evolution along the several lineages. These dissimilarities are most evident in comparisons between the phylogenetic depths of the Enterobacteriaceae and Vibrionaceae. Detection of disparate rates of evolution, as well as their influence on the interpretation of the natural taxonomy of this group of bacteria, is discussed.