Fig. 5: Evolution of PPE50 variants in the MTBC.
From: PPE50 variants as novel phylogeographic signatures of host-pathogen co-evolution in tuberculosis
PPE50 has evolved contrastingly between Ancient and Modern strains of the MTBC. PPE50-381 is the ancestral variant, being observed in M. canettii, and is the only PPE50 to be observed in Ancient and Modern MTBC strains. Recent expansion of Modern M. tuberculosis into lineages L2, L3 and L4 have seen marked diversity of PPE50 variants that are stably distributed in several sub-lineages that have spread globally. Whereas PPE50 variants in Ancient MTBC are mostly associated with Africa, except for L1. *Note: ppe50 is deleted in lineages L1, L4.1, and L4.2 and each are unique event polymorphisms. Maximum Likelihood tree (implemented in IQ-TREE). Bar indicates genetic distance nucleotide substitutions per site for each MTBC lineage/sub-lineage.
