Importantly, this ocular “”outlier”" (Nar/Dion (Left Eye)) retains 100% nucleotide similarity see more with the remaining isolates within the Narangba population, all of which were isolated from urogenital sites of infection. Coupled with the fact that isolate ‘Ned’ from the East Coomera population harbours
genetically distinct ocular and urogenital isolates of C. pecorum, this suggests that high rates of Selleck AZD3965 transmission within these confined koala populations may contribute to the transfer of C. pecorum from one body site to another and that the site of detection may not be the original niche of the strain . It appears that the tarP gene has potential as a phenotypic-dependent marker, however, importantly, further investigation is required that
utilises the full-length tarP gene (in conjunction with wider geographic sampling) to properly determine its true potential. From a full genome GSK2126458 in vivo evolutionary standpoint, the separation of the Brendale/Narangba populations from the Pine Creek/East Coomera populations is a distinction that is clearly mirrored in the overall phylogenetic analysis using concatenated data. This suggests that tarP, although having a relatively low rate of substitution, is capable of more accurately and specifically differentiating koala strains according to geography than ompA and ORF663, albeit with reduced resolution. For these reasons,
tarP also appears promising as an evolutionary indicator and may be classified as a “”neutral marker”", characterised by its selective constraints yet ability to reflect sequence diversity between koala populations that are geographically separate . However, as a “”neutral marker”", the tarP gene remains less useful when estimating a population’s adaptive potential Phosphoprotein phosphatase or local population divergence. ORF663 encodes a hypothetical protein and includes a 15 nucleotide variant coding tandem repeat (CTR) region that putatively associates it with a virulence-related role. Interestingly, this gene has not been identified in any other chlamydial species and BLAST search reveals no similarities to any other sequences in the database. The C. pecorum ORF663 gene was the most polymorphic gene among all investigated and represents a locus under considerable positive selection. Using this gene, we were able to observe the most distinctions between strains by identifying seven separate genotypes. These genotypes highlight the considerable discriminatory capacity of ORF663 which correlates with (while extending) the divisions made by ompA and tarP, by isolating the Narangba and Brendale populations into their own genotypes while separating the more heterogeneous Pine Creek and East Coomera populations into multiple genotypes.