1
|
Conti A, Casagrande Pierantoni D, Robert V, Corte L, Cardinali G. MinION Sequencing of Yeast Mock Communities To Assess the Effect of Databases and ITS-LSU Markers on the Reliability of Metabarcoding Analysis. Microbiol Spectr 2023; 11:e0105222. [PMID: 36519933 PMCID: PMC9927109 DOI: 10.1128/spectrum.01052-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Microbial communities play key roles both for humans and the environment. They are involved in ecosystem functions, maintaining their stability, and provide important services, such as carbon cycle and nitrogen cycle. Acting both as symbionts and as pathogens, description of the structure and composition of these communities is important. Metabarcoding uses ribosomal DNA (rDNA) (eukaryotic) or rRNA gene (prokaryotic) sequences for identification of species present in a site and measuring their abundance. This procedure requires several technical steps that could be source of bias producing a distorted view of the real community composition. In this work, we took advantage of an innovative "long-read" next-generation sequencing (NGS) technology (MinION) amplifying the DNA spanning from the internal transcribed spacer (ITS) to large subunit (LSU) that can be read simultaneously in this platform, providing more information than "short-read" systems. The experimental system consisted of six fungal mock communities composed of species present at various relative amounts to mimic natural situations characterized by predominant and low-frequency species. The influence of the sequencing platform (MinION and Illumina MiSeq) and the effect of different reference databases and marker sequences on metagenomic identification of species were evaluated. The results showed that the ITS-based database provided more accurate species identification than LSU. Furthermore, a procedure based on a preliminary identification with standard reference databases followed by the production of custom databases, including only the best outputs of the first step, is proposed. This additional step improved the estimate of species proportion of the mock communities and reduced the number of ghost species not really present in the simulated communities. IMPORTANCE Metagenomic analyses are fundamental in many research areas; therefore, improvement of methods and protocols for the description of microbial communities becomes more and more necessary. Long-read sequencing could be used for reducing biases due to the multicopy nature of rDNA sequences and short-read limitations. However, these novel technologies need to be assessed and standardized with controlled experiments, such as mock communities. The interest behind this work was to evaluate how long reads performed identification and quantification of species mixed in precise proportions and how the choice of database affects such analyses. Development of a pipeline that mitigates the effect of the barcoding sequences and the impact of the reference database on metagenomic analyses can help microbiome studies go one step further.
Collapse
Affiliation(s)
- Angela Conti
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
| | | | - Vincent Robert
- Westerdjik Institute for Biodiversity, Utrecht, Netherlands
| | - Laura Corte
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
- CEMIN Excellence Research Centre, Perugia, Italy
| | - Gianluigi Cardinali
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
- CEMIN Excellence Research Centre, Perugia, Italy
| |
Collapse
|
2
|
Boekhout T, Aime MC, Begerow D, Gabaldón T, Heitman J, Kemler M, Khayhan K, Lachance MA, Louis EJ, Sun S, Vu D, Yurkov A. The evolving species concepts used for yeasts: from phenotypes and genomes to speciation networks. FUNGAL DIVERS 2021; 109:27-55. [PMID: 34720775 PMCID: PMC8550739 DOI: 10.1007/s13225-021-00475-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 05/31/2021] [Indexed: 12/12/2022]
Abstract
Here we review how evolving species concepts have been applied to understand yeast diversity. Initially, a phenotypic species concept was utilized taking into consideration morphological aspects of colonies and cells, and growth profiles. Later the biological species concept was added, which applied data from mating experiments. Biophysical measurements of DNA similarity between isolates were an early measure that became more broadly applied with the advent of sequencing technology, leading to a sequence-based species concept using comparisons of parts of the ribosomal DNA. At present phylogenetic species concepts that employ sequence data of rDNA and other genes are universally applied in fungal taxonomy, including yeasts, because various studies revealed a relatively good correlation between the biological species concept and sequence divergence. The application of genome information is becoming increasingly common, and we strongly recommend the use of complete, rather than draft genomes to improve our understanding of species and their genome and genetic dynamics. Complete genomes allow in-depth comparisons on the evolvability of genomes and, consequently, of the species to which they belong. Hybridization seems a relatively common phenomenon and has been observed in all major fungal lineages that contain yeasts. Note that hybrids may greatly differ in their post-hybridization development. Future in-depth studies, initially using some model species or complexes may shift the traditional species concept as isolated clusters of genetically compatible isolates to a cohesive speciation network in which such clusters are interconnected by genetic processes, such as hybridization.
Collapse
Affiliation(s)
- Teun Boekhout
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
- Institute of Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, The Netherlands
| | - M. Catherine Aime
- Dept Botany and Plant Pathology, College of Agriculture, Purdue University, West Lafayette, IN 47907 USA
| | - Dominik Begerow
- Evolution of Plants and Fungi, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Toni Gabaldón
- Barcelona Supercomputing Centre (BSC–CNS), Jordi Girona, 29, 08034 Barcelona, Spain
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710 USA
| | - Martin Kemler
- Evolution of Plants and Fungi, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Kantarawee Khayhan
- Department of Microbiology and Parasitology, Faculty of Medical Sciences, University of Phayao, Phayao, 56000 Thailand
| | - Marc-André Lachance
- Department of Biology, University of Western Ontario, London, ON N6A 5B7 Canada
| | - Edward J. Louis
- Department of Genetics and Genome Biology, Genetic Architecture of Complex Traits, University of Leicester, Leicester, LE1 7RH UK
| | - Sheng Sun
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710 USA
| | - Duong Vu
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - Andrey Yurkov
- German Collection of Microorganisms and Cell Cultures, Leibniz Institute DSMZ, Brunswick, Germany
| |
Collapse
|