Bezuidt, Keoagile Ignatius OliverPierneef, Rian EwaldGomri, Amin M.Adesioye, Fiyinfoluwa AdenikeMakhalanyane, Thulani PeterKharroub, KarimaCowan, Don A.2016-07-072016-07-072016-05-24Bezuidt OK, Pierneef R, Gomri AM, Adesioye F, Makhalanyane TP, Kharroub K and Cowan DA (2016) The Geobacillus Pan-Genome: Implications for the Evolution of the Genus. Front. Microbiol. 7:723. DOI: 10.3389/fmicb.2016.00723.1664-302X10.3389/fmicb.2016.00723http://hdl.handle.net/2263/54161FIGURE S1 : Barplot of pan-genome matrix determined from the Geobacillus genomes.FIGURE S2 : Clusters of Orthologous Groups (COG) analysis of the Geobacillus pan-genome.FIGURE S3 : Heatmap comparison of the Geobacillus core genes against Anoxybacillus and Bacillus genomes.FIGURE S4 : Heatmap comparison of the Geobacillus soft-coregenes against Anoxybacillus and Bacillus genomes.FIGURE S5 : Heatmap comparison of the Geobacillus shell genes against Anoxybacillus and Bacillus genomes.FIGURE S6 : Heatmap comparison of the Geobacillus cloud genes against Anoxybacillus and Bacillus genomes.The genus Geobacillus is comprised of a diverse group of spore-forming Gram-positive thermophilic bacterial species and is well known for both its ecological diversity and as a source of novel thermostable enzymes. Although the mechanisms underlying the thermophilicity of the organism and the thermostability of its macromolecules are reasonably well understood, relatively little is known of the evolutionary mechanisms, which underlie the structural and functional properties of members of this genus. In this study, we have compared 29 Geobacillus genomes, with a specific focus on the elements, which comprise the conserved core and flexible genomes. Based on comparisons of conserved core and flexible genomes, we present evidence of habitat delineation with specific Geobacillus genomes linked to specific niches. Our analysis revealed that Geobacillus and Anoxybacillus share a high proportion of genes. Moreover, the results strongly suggest that horizontal gene transfer is a major factor deriving the evolution of Geobacillus from Bacillus, with genetic contributions from other phylogenetically distant taxa.en© 2016 Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).GeobacillusPan-genomeHorizontal gene transfer (HGT)Conserved coreFlexible genomesSoft coreArticle