Phylogeny-ontogeny correspondence in Bacillus subtilis biofilms
Links between ontogeny and phylogeny in animals have been discussed for more than two centuries. With the uprising of molecular biology and bioinformatics, several studies have revealed the presence of the phylogeny-ontogeny correlation in developmental transcriptomes of eukaryotic clades with complex multicellularity. These findings open a possibility to test the phylogeny-ontogeny correlation in more basal organisms, with more obscure development and multicellularity characteristics. Using time-resolved transcriptome and proteome profiles, this study showed that Bacillus subtilis biofilm ontogeny correlates with the evolutionary measures through recapitulation pattern, in a way that evolutionary younger and more diverged genes were increasingly expressed towards the later timepoints of the biofilm growth. Molecular and morphological signatures also revealed that biofilm growth is highly regulated and organized into discrete ontogenetic stages. Together, this suggests that the biofilm formation in Bacillus subtilis is a true developmental process comparable to organismal development in animals, plants and fungi.