065), and incA (p = 0.016), which is anticipated given the expected contrast between the genetic
variation present in our koala populations and the global samples of C. www.selleckchem.com/products/Adriamycin.html pecorum from multiple animal hosts. Interestingly, the tarP gene produced a comparable figure of p = 0.028. These results are significant from a global C. pecorum genetic diversity perspective, but this remains outside the scope of this study. In the context of the current study, this data importantly demonstrated that the incA value of p = 0.016 for the koala populations is below the p = 0.02 threshold required for intra-species differentiation. Examination of the resulting phylogenetic trees revealed a level of resolution that was consistent with the corresponding gene’s AZD3965 mw mean nucleotide diversity within the koala strains (Figure 1). Between each of the four trees there remained a consistent dissimilarity of branching orders, each with
varying degrees of bootstrap support. SC75741 datasheet Overall, there was a tendency for ompA and ORF663 to separate the Narangba and Brendale populations from the East Coomera and Pine Creek populations, while the tarP phylogenetic tree provided the most robust evidence for this distinction (Figure 1). The incA tree revealed less resolution between C. pecorum positive samples, correlating with its low level of mean sequence diversity and discriminatory power (Table 3). Figure 1 Mid-point rooted phylogenetic trees based on each of the four candidate for genes. Inferred by the neighbour-joining method with bootstrapping support (1000 replicates). a) ompA; b) incA; c) tarP; d) ORF663. To create a more comprehensive data set to permit more robust phylogenetic inferences, sequences for each of
the four genes were concatenated and used in the construction of an additional phylogenetic tree (Figure 2). This tree produced largely similar groupings to those described above with the separation of the Narangba and Brendale populations from the Pine Creek and East Coomera populations, as well as the isolation of the more divergent C. pecorum positive samples from their respective populations. To test whether the phylogeny resulting from the concatenated sequence was biased by a single locus, a subset of trees was built using the concatenated data with each region omitted. This resulted in no perturbation of the tree topology (data not shown). Figure 2 Phylogenetic tree from concatenated sequences of omp A, inc A, ORF663, and tar P from all koala populations. Mid-point rooted and inferred by the neighbour-joining method with bootstrapping support (1000 replicates). In addition, a phylogenetic analysis was performed to examine the relationship between the koala C. pecorum samples analysed in this study, and other previously sequenced strains from non-koala hosts (Table 1). Initially a tree was constructed using only ompA data (Figure 3) which clearly shows the koala C. pecorum sequences grouping with sheep and/or cattle strains rather than with each other.