Assessing the diversity and distribution of apicomplexans in host and free-living environments using high-throughput amplicon data and a phylogenetically informed reference framework

del Campo, Javier (Department of Botany, University of British Columbia, Vancouver, BC, Canada ; Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States) ; Heger, Thierry J. (Department of Botany, University of British Columbia, Vancouver, BC, Canada ; School of Viticulture and Enology, HES-SO // University of Applied Sciences Western Switzerland) ; Rodriguez-Martinez, Raquel (Department of Biosciences, Living Systems Institute, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom) ; Worden, Alexandra Z. (GEOMAR – Helmholtz Centre for Ocean Research Kiel, Kiel, Germany) ; Richards, Thomas A. (Department of Biosciences, Living Systems Institute, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom) ; Massana, Ramon (Department of Marine Biology and Oceanography, Institut de Ciències del Mar (CSIC), Barcelona, Spain) ; Keeling, Patrick J. (Department of Botany, University of British Columbia, Vancouver, BC, Canada)

Apicomplexans are a group of microbial eukaryotes that contain some of the most well-studied parasites, including the causing agents of toxoplasmosis and malaria, and emergent diseases like cryptosporidiosis or babesiosis. Decades of research have illuminated the pathogenic mechanisms, molecular biology, and genomics of model apicomplexans, but we know little about their diversity and distribution in natural environments. In this study we analyze the distribution of apicomplexans across a range of both host-associated and free-living environments. Using publicly available small subunit (SSU) rRNA gene databases, high-throughput environmental sequencing (HTES) surveys, and our own generated HTES data, we developed an apicomplexan reference database, which includes the largest apicomplexan SSU rRNA tree available to date and encompasses comprehensive sampling of this group and their closest relatives. This tree allowed us to identify and correct incongruences in the molecular identification of apicomplexan sequences. Analyzing the diversity and distribution of apicomplexans in HTES studies with this curated reference database also showed a widespread, and quantitatively important, presence of apicomplexans across a variety of free-living environments. These data allow us to describe a remarkable molecular diversity of this group compared with our current knowledge, especially when compared with that identified from described apicomplexan species. This is most striking in marine environments, where potentially the most diverse apicomplexans apparently exist, but have not yet been formally recognized. The new database will be useful for microbial ecology and epidemiological studies, and provide valuable reference for medical and veterinary diagnosis especially in cases of emerging, zoonotic, and cryptic infections.


Keywords:
Article Type:
scientifique
Faculty:
Ingénierie et Architecture
School:
Changins
Institute:
Aucun institut
Date:
2019-10
Pagination:
15 p.
Published in:
Frontiers in Microbiology
Numeration (vol. no.):
2019, vol. 10, article no. 2373
DOI:
ISSN:
1664-302X
Appears in Collection:



 Record created 2019-10-29, last modified 2019-11-05

Fulltext:
Download fulltext
PDF

Rate this document:

Rate this document:
1
2
3
 
(Not yet reviewed)