One of the most important measures for detecting molecular adaptations between species/lineages at the gene level is the comparison of relative fixation rates of synonymous (dS) and non-synonymous (dN) mutations. This study shows that the branch model is sensitive to tree topology and proposes an alternative approach, devogs, which does not require phylogenetic topology for analysis. We compared devogs with a branch model method using virtual data and a varying ω ratio, in which parameters were obtained from real data. The positive predictive value, sensitivity, and specificity of the branch model were affected by the phylogenic tree topology. Devogs showed greater positive predictive value, whereas the branch model method had greater sensitivity. In a working example using devogs, a group of human RNA polymerase II-related genes, which are important in mediating alternative splicing, were significantly accelerated compared to four other mammals.

Using a newly constructed de novo assembly pipeline, finished genome level assembly had been conducted for the probiotic candidate strain E. faecalis KACC 91532 isolated from a stool samples of Korean neonates. Our gene prediction identified 3, 061 genes in the assembled genome of the strain. Among these, nine genes were specific only for the E. faecalis KACC 91532, compared with all of the four known reference genomes (EF62, D32, V583, OG1RF). We identified genes related to phenotypic characters and detected E. faecalis KACC 91532-specific evolutionarily accelerated genes using dN/dS analysis. From these results, we found the potential risk of KACC 91532 as a useful probiotic strain and identified some candidate genetic variations that could affect the function of enzymes.