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ABSTRACT Mycobacterium bovisandMycobacterium tuberculosisare the most relevant among pathogenic mycobacteria, both belonging to theM. tuberculosiscomplex (MTC). Samples of blood, liver, spleen, kidneys, lungs and caseous tubercles were collected from a free‐ranging juvenile black capuchin monkey (Sapajus nigritus) showing non‐specific signs of illness. Macroscopic findings included emaciation, a caseous lesion in a tooth and gingiva, disseminated nodules in both lungs and left kidney parenchyma and caseous nodules on the pleura and mesentery. The lesions suggested MTC infection, a diagnosis subsequently supported in the lung by bacilloscopy, immunochromatography and PCR. A multiplex PCR further validated the presence ofM. bovisgenes. Cases of tuberculosis in platyrrhine primates have only been reported in animals maintained in captivity. We describe for the first time the pathological and molecular findings ofM. bovisinfection in a free‐ranging platyrrhine monkey within an area of intense human–wildlife interaction, which has important implications from a One Health perspective.
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The impact of frequently neglected model violations on bacterial recombination rate estimation: a case study in Mycobacterium canettii and Mycobacterium tuberculosis
Abstract Mycobacterium canettii is a causative agent of tuberculosis in humans, along with the members of the Mycobacterium tuberculosis complex. Frequently used as an outgroup to the M. tuberculosis complex in phylogenetic analyses, M. canettii is thought to offer the best proxy for the progenitor species that gave rise to the complex. Here, we leverage whole-genome sequencing data and biologically relevant population genomic models to compare the evolutionary dynamics driving variation in the recombining M. canettii with that in the nonrecombining M. tuberculosis complex, and discuss differences in observed genomic diversity in the light of expected levels of Hill–Robertson interference. In doing so, we highlight the methodological challenges of estimating recombination rates through traditional population genetic approaches using sequences called from populations of microorganisms and evaluate the likely mis-inference that arises owing to a neglect of common model violations including purifying selection, background selection, progeny skew, and population size change. In addition, we compare performance when full within-host polymorphism data are utilized, versus the more common approach of basing analyses on within-host consensus sequences.
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- Award ID(s):
- 2045343
- PAR ID:
- 10390244
- Editor(s):
- Wong, A
- Date Published:
- Journal Name:
- G3 Genes|Genomes|Genetics
- Volume:
- 12
- Issue:
- 5
- ISSN:
- 2160-1836
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/g3journal/jkac055
