FIG 1.
Gene synteny, membrane topology, and sequence homology of LCT-associated holin-like proteins in clostridia. (A) Gene organization in LCT PaLocs and a bacteriocin-containing operon. Light blue, LCTs and bacteriocin; yellow, sigma factors; orange, holin-like proteins. Gene lengths are not to scale. (B) Proposed membrane topology of holins and holin-like proteins from panel A and twin-arginine transport (Tat) proteins. TatA and TatE are from E. coli, and TatAd is from B. subtilis. (C) Sequence alignments of holin-like proteins. The proteins were aligned using the ClustalW algorithm in the MegAlign software suite, part of the Lasergene 16 DNA analysis package from DNAStar. Residues that match the TpeE sequence are highlighted in yellow shading. Note that there are 7 residue differences between TpeE and UviB. GenBank sequence accession numbers are as follows: WP_003453321.1 for C. perfringens TpeE, ABG87870.1 for C. perfringens UviB, WP_105463372.1 for E. coli TatE, and QNN28895.1 for B. subtilis TatAd. The PDB ID for E. coli TatA is 2MN7_A.