Despite its ubiquitous infectivity to mammals with strong host specificity, our current knowledge about
Pneumocystis has originated from studies of merely 4% of extant mammalian species. Further studies of
Pneumocystis epidemiology across a broader range of animal species require the use of assays
[...] Read more.
Despite its ubiquitous infectivity to mammals with strong host specificity, our current knowledge about
Pneumocystis has originated from studies of merely 4% of extant mammalian species. Further studies of
Pneumocystis epidemiology across a broader range of animal species require the use of assays with high sensitivity and specificity. To this end, we have developed multiple universal
Pneumocystis primers targeting different genetic loci with high amplification efficiency. Application of these primers to PCR investigation of
Pneumocystis in free-living hares (
Lepus townsendii,
n = 130) and rabbits (
Oryctolagus cuniculus,
n = 8) in Canada revealed a prevalence of 81% (105/130) and 25% (2/8), respectively. Genotyping analysis identified five and two variants of
Pneumocystis from hares and rabbits, respectively, with significant sequence divergence between the variants from hares. Based on phylogenetic analysis using nearly full-length sequences of the mitochondrial genome, nuclear rRNA operon and dihydropteroate synthase gene for the two most common variants,
Pneumocystis in hares and rabbits are more closely related to each other than either are to
Pneumocystis in other mammals. Furthermore,
Pneumocystis in both hares and rabbits are more closely related to
Pneumocystis in primates and dogs than to
Pneumocystis in rodents. The high prevalence of
Pneumocystis in hares (
P. sp. ‘
townsendii’) suggests its widespread transmissibility in the natural environment, similar to
P. oryctolagi in rabbits. The presence of multiple distinct
Pneumocystis populations in hares contrasts with the lack of apparent intra-species heterogeneity in
P. oryctolagi, implying a unique evolution history of
P. sp. ‘
townsendii’ in hares.
Full article