Cartoons of tree topologies showing major NRPS subfamilies. All trees reflect phylogenetic analyses of the complete A domain dataset. A. NJ tree using a ML distance matrix created using the WAG plus gamma model. B. ML tree (PhyML) using the WAG plus gamma model. C. ML tree (RAxML) using the RTREVF plus gamma model. Bootstrap support greater than 50% is shown under branches. The light blue rectangle indicates primarily mono/bi-modular NRPS; the SID and EAS subclasses are primarily multimodular. Color coding for subfamilies: brown: adenylating enzyme outgroups; light green: fungal PKS;NRPS hybrid synthetases (PKS;NRPS); dark orange: ChNPS11/ETP module 1 synthetases (ChNPS11/ETP mod 1); dark blue: ChNPS12/ETP module 2 synthetases (ChNPS12/ETP mod 2); yellow: ChNPS10-like synthetases (ChNPS10); light blue: Cyclosporin synthetases (CYCLO); pink: α-aminoadipate reductases (AAR); dark green: ACV synthetases (ACV); red: siderophore synthetases (SID); purple: Euascomycete clade synthetases (EAS). The majority of bacterial sequences (dark gray) group together although they contain a few fungal A domains (ACV synthetases and the NRPS;PKS hybrid (ChNPS7;PKS24) suspected of being horizontally transmitted from bacteria to fungi. The remaining bacterial A domains group with the mono/bi-modular AAR and ChNPS12/ETP mod 2 subfamilies.