Schematic of the hit loci in Mollicutes and Chlamydiaceae . A schematic representation of genes within the hit loci of the following species: A) M. pulmonis, M. mycoides subsp. mycoides SC, Mesoplasma florum and M. mobile containing genes homologous to hit ABL of M. hominis; B) U. parvum, M. pneumoniae and M. genitalium, each containing a gene upstream of hit L predicted to encode an integral pore-forming protein; and C) C. pneumoniae, C. trachomatis, C. muridarum and C. caviae containing hit L flanking genes predicted to encode, upstream, a protein with the signature sequence of a metal-dependent hydrolase (light blue region), with an OB nucleic acid binding fold (dark blue region) and, downstream, a protein with ARM repeats (red regions), which are known to mediate protein-protein interactions. Triangles indicate signal peptidase recognition sites of SPase I and SPase II. Transmembrane regions are depicted as striped regions. The position of the RGD tri-peptide is marked by a dotted region.