Comparison of the putative topological organization of bacterial and mitochondrial TSPO.

<p>(a) <i>Pseudomonas fluorescens</i> MF37 bactTSPO. (b) BactTSPO from <i>Rhodobacter sphaeroides</i> 2.4.1 recalculated from Yeliseev and Kaplan <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006096#pone.0006096-Yeliseev3" target="_blank">[12]</a>. (c) Mitochondrial TSPO <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006096#pone.0006096-JosephLiauzun1" target="_blank">[13]</a>. <i>P. fluorescens</i> MF37 bactTSPO has a typical five transmembrane helix structure, a larger L1 intra-cytoplasmic loop, and an extended cytoplasmic C-terminal end. In contrast, the extracellular N-terminal end is absent, and a peptidoglycane binding domain signature is present between the L2 loop and H3 transmembrane domain.</p>