Fig. 5.

Domain organization and bioinformatic prediction of SitAI functions. (A) Domain organization of representative sequences of a modular and polymorphic SitA family (SitA5) and a polymorphic family (SitA4). Note that the SitA5 family has a nonconserved CTD, i.e., different domain modules compared to the conserved CTD of SitA4. Conservation scores are based on an algorithm that takes into account conservation of physicochemical properties of individual residues (52). Proteins not shown to scale. (B) Functional prediction of all uniquely clustering toxin domains found in Myxococcales sitA alleles by HHpred. The top relevant domain hit is shown, with preference given to Pfam domains deposited in comprehensive domain analyses (15, 32). Search criteria are described in Materials and Methods, and additional details, including HHpred probability score, domain size, and SitI functional predictions, are provided in SI Appendix, Table S5. Domains are shown to scale. Domains followed by a number are to distinguish those that share a common domain prediction despite having very little sequence similarity.