ADP-ribosyltransferases (ADPRTs) in segmented filamentous bacteria (SFB). (A) Phylogenetic tree based on four ADPRT sequence types from SFB and ADPRTs from other Firmicutes. Proteins were aligned using MUSCLE, all columns with gaps removed, and phylogeny inferred using a maximum likelihood method. Bootstrap statistical support for branchings with values ≥70 are shown. SFB ADPRT Type-1, SFBSU_002P79; SFB ADPRT Type-2, SFBSU_006P112; SFB ADPRT Type-3, SFBSU_007P84; SFB ADPRT Type-4, SFBM_0768; EFV toxin Enterococcus faecalis V583, NP_814127; Iota toxin Clostridium perfringens, Q46220; Vip2 Bacillus cereus, 1QS1_A. (B) Protein domain organization of the four ADPRTs in SFB. (PF03496) ADP-ribosyltransferase domain; (PF04233) phage protein-like domain. See Figure 3, and Supplemental Figure S12 for information about their localization in SFB genomes, respectively. (C) Amino acid sequence conservation among SFB ADPRT sequence types. (*) Key amino acid residues, involved in catalysis as described for the C. perfringens iota toxin (Y246, Y251, N255, R295, S338-S340, F349, E378, E380) (Tsuge et al. 2008).
