Sequence, structure prediction, and epitope analysis of the polymorphic membrane protein family in Chlamydia trachomatis
Fig 5
Pmp passenger domains form a regular β-helical structure.
Pmp passenger domain structural models and nomenclature illustrating the parallel β-sheets (PB) and turns (T). (A) Family portrait of Pmp passenger domain models. From left to right: PmpA, B, C, D, E, F, G, H, and I. (B) PmpD passenger domain showing 22 complete β-helix coils. (C) PmpD passenger domain cross section between amino acid residues 615–641 shows how the repeat sequence forms the core of the β-helix. Note that the nomenclature used here follows the well-established numbering by Yoder et al., 1993 and Jenkins et al., 2001 [80, 81], rather than the one proposed by [45]. The parallel β-sheet PB1 is shown in yellow, PB2 in blue, PB3 in red. The GGA(I,L,V) and FxxN motifs are bolded—in this case we have GGAL at the transition from T3 to PB1, and FSRN at the transition from PB3 to T3. (D) π-stacking interactions between the conserved phenylalanines may help stabilize the core of the β-helix.