1
|
Lind AL, McDonald NA, Gerrick ER, Bhatt AS, Pollard KS. Hybrid assemblies of microbiome Blastocystis protists reveal evolutionary diversification reflecting host ecology. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.20.567959. [PMID: 38045412 PMCID: PMC10690189 DOI: 10.1101/2023.11.20.567959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
The most prevalent microbial eukaryote in the human gut is Blastocystis , an obligate commensal protist also common in many other vertebrates. Blastocystis is descended from free-living stramenopile ancestors; how it has adapted to thrive within humans and a wide range of hosts is unclear. Here, we cultivated six Blastocystis strains spanning the diversity of the genus and generated highly contiguous, annotated genomes with long-read DNA-seq, Hi-C, and RNA-seq. Comparative genomics between these strains and two closely related stramenopiles with different lifestyles, the lizard gut symbiont Proteromonas lacertae and the free-living marine flagellate Cafeteria burkhardae , reveal the evolutionary history of the Blastocystis genus. We find substantial gene content variability between Blastocystis strains. Blastocystis isolated from an herbivorous tortoise has many plant carbohydrate metabolizing enzymes, some horizontally acquired from bacteria, likely reflecting fermentation within the host gut. In contrast, human- isolated Blastocystis have gained many heat shock proteins, and we find numerous subtype- specific expansions of host-interfacing genes, including cell adhesion and cell surface glycan genes. In addition, we observe that human-isolated Blastocystis have substantial changes in gene structure, including shortened introns and intergenic regions, as well as genes lacking canonical termination codons. Finally, our data indicate that the common ancestor of Blastocystis lost nearly all ancestral genes for heterokont flagella morphology, including cilia proteins, microtubule motor proteins, and ion channel proteins. Together, these findings underscore the huge functional variability within the Blastocystis genus and provide candidate genes for the adaptations these lineages have undergone to thrive in the gut microbiomes of diverse vertebrates.
Collapse
|
2
|
Záhonová K, Low RS, Warren CJ, Cantoni D, Herman EK, Yiangou L, Ribeiro CA, Phanprasert Y, Brown IR, Rueckert S, Baker NL, Tachezy J, Betts EL, Gentekaki E, van der Giezen M, Clark CG, Jackson AP, Dacks JB, Tsaousis AD. Evolutionary analysis of cellular reduction and anaerobicity in the hyper-prevalent gut microbe Blastocystis. Curr Biol 2023:S0960-9822(23)00620-6. [PMID: 37267944 DOI: 10.1016/j.cub.2023.05.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 03/22/2023] [Accepted: 05/11/2023] [Indexed: 06/04/2023]
Abstract
Blastocystis is the most prevalent microbial eukaryote in the human and animal gut, yet its role as commensal or parasite is still under debate. Blastocystis has clearly undergone evolutionary adaptation to the gut environment and possesses minimal cellular compartmentalization, reduced anaerobic mitochondria, no flagella, and no reported peroxisomes. To address this poorly understood evolutionary transition, we have taken a multi-disciplinary approach to characterize Proteromonas lacertae, the closest canonical stramenopile relative of Blastocystis. Genomic data reveal an abundance of unique genes in P. lacertae but also reductive evolution of the genomic complement in Blastocystis. Comparative genomic analysis sheds light on flagellar evolution, including 37 new candidate components implicated with mastigonemes, the stramenopile morphological hallmark. The P. lacertae membrane-trafficking system (MTS) complement is only slightly more canonical than that of Blastocystis, but notably, we identified that both organisms encode the complete enigmatic endocytic TSET complex, a first for the entire stramenopile lineage. Investigation also details the modulation of mitochondrial composition and metabolism in both P. lacertae and Blastocystis. Unexpectedly, we identify in P. lacertae the most reduced peroxisome-derived organelle reported to date, which leads us to speculate on a mechanism of constraint guiding the dynamics of peroxisome-mitochondrion reductive evolution on the path to anaerobiosis. Overall, these analyses provide a launching point to investigate organellar evolution and reveal in detail the evolutionary path that Blastocystis has taken from a canonical flagellated protist to the hyper-divergent and hyper-prevalent animal and human gut microbe.
Collapse
Affiliation(s)
- Kristína Záhonová
- Division of Infectious Diseases, Department of Medicine, University of Alberta, 1-124 Clinical Sciences Building, 11350-83 Avenue, Edmonton T6G 2G3, Canada; Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 1160/31, České Budějovice (Budweis) 370 05, Czech Republic; Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Průmyslová 595, Vestec 252 50, Czech Republic; Life Science Research Centre, Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho 10, Ostrava 710 00, Czech Republic
| | - Ross S Low
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK; The Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK
| | - Christopher J Warren
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK
| | - Diego Cantoni
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK
| | - Emily K Herman
- Division of Infectious Diseases, Department of Medicine, University of Alberta, 1-124 Clinical Sciences Building, 11350-83 Avenue, Edmonton T6G 2G3, Canada; Department of Agricultural, Food, and Nutritional Science, Faculty of Agricultural, Life, and Environmental Sciences, University of Alberta, 2-31 General Services Building, Edmonton, AB T6G 2H1, Canada
| | - Lyto Yiangou
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK
| | - Cláudia A Ribeiro
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK
| | - Yasinee Phanprasert
- Division of Infectious Diseases, Department of Medicine, University of Alberta, 1-124 Clinical Sciences Building, 11350-83 Avenue, Edmonton T6G 2G3, Canada; School of Science, Mae Fah Luang Universit, 333 Moo 1, T. Tasud, Muang District, Chiang Rai 57100, Thailand
| | - Ian R Brown
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK
| | - Sonja Rueckert
- School of Applied Sciences, Sighthill Campus, Room 3.B.36, Edinburgh EH11 4BN, Scotland; Faculty of Biology, AG Eukaryotische Mikrobiologie, Universitätsstrasse 5, S05 R04 H83, Essen 45141, Germany
| | - Nicola L Baker
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK
| | - Jan Tachezy
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Průmyslová 595, Vestec 252 50, Czech Republic
| | - Emma L Betts
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK; School of Applied Sciences, Sighthill Campus, Room 3.B.36, Edinburgh EH11 4BN, Scotland
| | - Eleni Gentekaki
- School of Science, Mae Fah Luang Universit, 333 Moo 1, T. Tasud, Muang District, Chiang Rai 57100, Thailand; Gut Microbiome Research Group, Mae Fah Luang University, 333 Moo 1, T. Tasud, Muang District, Chiang Rai 57100, Thailand
| | - Mark van der Giezen
- Department of Chemistry, Bioscience and Environmental Engineering, University of Stavanger Richard Johnsens Gate 4, 4021 Stavanger, Norway; Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - C Graham Clark
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Andrew P Jackson
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Joel B Dacks
- Division of Infectious Diseases, Department of Medicine, University of Alberta, 1-124 Clinical Sciences Building, 11350-83 Avenue, Edmonton T6G 2G3, Canada; Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 1160/31, České Budějovice (Budweis) 370 05, Czech Republic; Centre for Life's Origin and Evolution, Division of Biosciences, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK.
| | - Anastasios D Tsaousis
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Giles Lane, Stacey Building, Canterbury, Kent CT2 7NJ, UK.
| |
Collapse
|
3
|
Li FJ, Tsaousis AD, Purton T, Chow VTK, He CY, Tan KSW. Successful Genetic Transfection of the Colonic Protistan Parasite Blastocystis for Reliable Expression of Ectopic Genes. Sci Rep 2019; 9:3159. [PMID: 30816225 PMCID: PMC6395660 DOI: 10.1038/s41598-019-39094-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/17/2019] [Indexed: 02/06/2023] Open
Abstract
The microbial parasite Blastocystis colonizes the large intestines of numerous animal species and increasing evidence has linked Blastocystis infection to enteric diseases with signs and symptoms including abdominal pain, constipation, diarrhea, nausea, vomiting, and flatulence. It has also recently been reported to be an important member of the host intestinal microbiota. Despite significant advances in our understanding of Blastocystis cell biology and host-parasite interactions, a genetic modification tool is absent. In this study, we successfully established a robust gene delivery protocol for Blastocystis subtype 7 (ST7) and ectopic protein expression was further tested using a high sensitivity nano-luciferase (Nluc) reporter system, with promoter regions from several genes. Among them, a strong promoter encompassing a region upstream of the legumain 5' UTR was identified. Using this promoter combined with the legumain 3' UTR, which contains a conserved, precise polyadenylation signal, a robust transient transfection technique was established for the first time in Blastocystis. This system was validated by ectopic expression of proteins harbouring specific localization signals. The establishment of a robust, reproducible gene modification system for Blastocystis is a significant advance for Blastocystis research both in vitro and in vivo. This technique will spearhead further research to understand the parasite's biology, its role in health and disease, along with novel ways to combat the parasite.
Collapse
Affiliation(s)
- Feng-Jun Li
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore, 117545, Singapore.,Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Anastasios D Tsaousis
- Laboratory of Molecular and Evolutionary Parasitology, RAPID group, School of Biosciences, University of Kent, Canterbury, CT2 7NJ, United Kingdom
| | - Tracy Purton
- Laboratory of Molecular and Evolutionary Parasitology, RAPID group, School of Biosciences, University of Kent, Canterbury, CT2 7NJ, United Kingdom
| | - Vincent T K Chow
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore, 117545, Singapore
| | - Cynthia Y He
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
| | - Kevin S W Tan
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore, 117545, Singapore.
| |
Collapse
|
4
|
Characterization of mRNA polyadenylation in the apicomplexa. PLoS One 2018; 13:e0203317. [PMID: 30161237 PMCID: PMC6117058 DOI: 10.1371/journal.pone.0203317] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 08/18/2018] [Indexed: 11/19/2022] Open
Abstract
Messenger RNA polyadenylation is a universal aspect of gene expression in eukaryotes. In well-established model organisms, this process is mediated by a conserved complex of 15–20 subunits. To better understand this process in apicomplexans, a group of unicellular parasites that causes serious disease in humans and livestock, a computational and high throughput sequencing study of the polyadenylation complex and poly(A) sites in several species was conducted. BLAST-based searches for orthologs of the human polyadenylation complex yielded clear matches to only two—poly(A) polymerase and CPSF73—of the 19 proteins used as queries in this analysis. As the human subunits that recognize the AAUAAA polyadenylation signal (PAS) were not immediately obvious, a computational analysis of sequences adjacent to experimentally-determined apicomplexan poly(A) sites was conducted. The results of this study showed that there exists in apicomplexans an A-rich region that corresponds in position to the AAUAAA PAS. The set of experimentally-determined sites in one species, Sarcocystis neurona, was further analyzed to evaluate the extent and significance of alternative poly(A) site choice in this organism. The results showed that almost 80% of S. neurona genes possess more than one poly(A) site, and that more than 780 sites showed differential usage in the two developmental stages–extracellular merozoites and intracellular schizonts–studied. These sites affected more than 450 genes, and included a disproportionate number of genes that encode membrane transporters and ribosomal proteins. Taken together, these results reveal that apicomplexan species seem to possess a poly(A) signal analogous to AAUAAA even though genes that may encode obvious counterparts of the AAUAAA-recognizing proteins are absent in these organisms. They also indicate that, as is the case in other eukaryotes, alternative polyadenylation is a widespread phenomenon in S. neurona that has the potential to impact growth and development.
Collapse
|
5
|
Armengaud J, Pible O, Gaillard JC, Cian A, Gantois N, Tan KSW, Chabé M, Viscogliosi E. Proteogenomic Insights into the Intestinal Parasite Blastocystis
sp. Subtype 4 Isolate WR1. Proteomics 2017; 17. [DOI: 10.1002/pmic.201700211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 08/09/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Jean Armengaud
- Laboratoire Innovations technologiques pour la Détection et le Diagnostic (Li2D); Service de Pharmacologie et Immunoanalyse (SPI); CEA, INRA; Gif-Sur-Yvette France
| | - Olivier Pible
- Laboratoire Innovations technologiques pour la Détection et le Diagnostic (Li2D); Service de Pharmacologie et Immunoanalyse (SPI); CEA, INRA; Gif-Sur-Yvette France
| | - Jean-Charles Gaillard
- Laboratoire Innovations technologiques pour la Détection et le Diagnostic (Li2D); Service de Pharmacologie et Immunoanalyse (SPI); CEA, INRA; Gif-Sur-Yvette France
| | - Amandine Cian
- Université de Lille; CNRS, Inserm, CHU Lille; Institut Pasteur de Lille; U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille; 1 rue du Professeur Calmette, Lille, France
| | - Nausicaa Gantois
- Université de Lille; CNRS, Inserm, CHU Lille; Institut Pasteur de Lille; U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille; 1 rue du Professeur Calmette, Lille, France
| | - Kevin S. W. Tan
- Laboratory of Molecular and Cellular Parasitology; Department of Microbiology and Immunology; Yong Loo Lin School of Medicine; National University of Singapore; Singapore Singapore
| | - Magali Chabé
- Université de Lille; CNRS, Inserm, CHU Lille; Institut Pasteur de Lille; U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille; 1 rue du Professeur Calmette, Lille, France
| | - Eric Viscogliosi
- Université de Lille; CNRS, Inserm, CHU Lille; Institut Pasteur de Lille; U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille; 1 rue du Professeur Calmette, Lille, France
| |
Collapse
|
6
|
Hondermarck H. Proteogenomics Gets onto the Regulation of mRNA Decoding and Translation into Protein. Proteomics 2017; 17. [PMID: 28990322 DOI: 10.1002/pmic.201700315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 10/09/2017] [Indexed: 11/09/2022]
Abstract
Proteogenomics, the integrative analysis of the proteome and the genome, increasingly provides protein-level insights about the regulation of gene expression and protein translation. Armengaud et al. (Proteomics 2017, 17, 1700211) nicely illustrate this trend with the first in-depth proteomic analysis of the eukaryotic and unicellular intestinal parasite Blastocystis sp. Not only this work constitutes an important milestone toward the proteogenomics profile of this human pathogen, but also it demonstrates at the protein level the occurrence of a specific mechanism of mRNA decoding. GU-rich motifs located downstream of mRNA polyadenylation sites create termination codons that ultimately result in the synthesis of proteins with lower molecular weight than predicted from gene sequence. Thus, the scope of proteogenomics now extends to the regulation of mRNA translation into proteins, providing a proof of concept for future studies in multicellular eukaryotes such as humans and plants.
Collapse
Affiliation(s)
- Hubert Hondermarck
- School of Biomedical Sciences and Pharmacy & Hunter Medical Research Institute, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia
| |
Collapse
|
7
|
Gentekaki E, Curtis BA, Stairs CW, Klimeš V, Eliáš M, Salas-Leiva DE, Herman EK, Eme L, Arias MC, Henrissat B, Hilliou F, Klute MJ, Suga H, Malik SB, Pightling AW, Kolisko M, Rachubinski RA, Schlacht A, Soanes DM, Tsaousis AD, Archibald JM, Ball SG, Dacks JB, Clark CG, van der Giezen M, Roger AJ. Extreme genome diversity in the hyper-prevalent parasitic eukaryote Blastocystis. PLoS Biol 2017; 15:e2003769. [PMID: 28892507 PMCID: PMC5608401 DOI: 10.1371/journal.pbio.2003769] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/21/2017] [Accepted: 08/25/2017] [Indexed: 12/11/2022] Open
Abstract
Blastocystis is the most prevalent eukaryotic microbe colonizing the human gut, infecting approximately 1 billion individuals worldwide. Although Blastocystis has been linked to intestinal disorders, its pathogenicity remains controversial because most carriers are asymptomatic. Here, the genome sequence of Blastocystis subtype (ST) 1 is presented and compared to previously published sequences for ST4 and ST7. Despite a conserved core of genes, there is unexpected diversity between these STs in terms of their genome sizes, guanine-cytosine (GC) content, intron numbers, and gene content. ST1 has 6,544 protein-coding genes, which is several hundred more than reported for ST4 and ST7. The percentage of proteins unique to each ST ranges from 6.2% to 20.5%, greatly exceeding the differences observed within parasite genera. Orthologous proteins also display extreme divergence in amino acid sequence identity between STs (i.e., 59%-61% median identity), on par with observations of the most distantly related species pairs of parasite genera. The STs also display substantial variation in gene family distributions and sizes, especially for protein kinase and protease gene families, which could reflect differences in virulence. It remains to be seen to what extent these inter-ST differences persist at the intra-ST level. A full 26% of genes in ST1 have stop codons that are created on the mRNA level by a novel polyadenylation mechanism found only in Blastocystis. Reconstructions of pathways and organellar systems revealed that ST1 has a relatively complete membrane-trafficking system and a near-complete meiotic toolkit, possibly indicating a sexual cycle. Unlike some intestinal protistan parasites, Blastocystis ST1 has near-complete de novo pyrimidine, purine, and thiamine biosynthesis pathways and is unique amongst studied stramenopiles in being able to metabolize α-glucans rather than β-glucans. It lacks all genes encoding heme-containing cytochrome P450 proteins. Predictions of the mitochondrion-related organelle (MRO) proteome reveal an expanded repertoire of functions, including lipid, cofactor, and vitamin biosynthesis, as well as proteins that may be involved in regulating mitochondrial morphology and MRO/endoplasmic reticulum (ER) interactions. In sharp contrast, genes for peroxisome-associated functions are absent, suggesting Blastocystis STs lack this organelle. Overall, this study provides an important window into the biology of Blastocystis, showcasing significant differences between STs that can guide future experimental investigations into differences in their virulence and clarifying the roles of these organisms in gut health and disease.
Collapse
Affiliation(s)
- Eleni Gentekaki
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Bruce A. Curtis
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Courtney W. Stairs
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Vladimír Klimeš
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Marek Eliáš
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Dayana E. Salas-Leiva
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Emily K. Herman
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Laura Eme
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Maria C. Arias
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, UMR8576 CNRS-USTL, Cité Scientifique, Villeneuve d’Ascq Cedex, France
| | - Bernard Henrissat
- CNRS UMR 7257, Aix-Marseille University, Marseille, France
- INRA, USC 1408 AFMB, Marseille, France
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Mary J. Klute
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Hiroshi Suga
- Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Nanatsuka 562, Shobara, Hiroshima, Japan
| | - Shehre-Banoo Malik
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Arthur W. Pightling
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Martin Kolisko
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | - Alexander Schlacht
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Darren M. Soanes
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Anastasios D. Tsaousis
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - John M. Archibald
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
- Canadian Institute for Advanced Research, CIFAR Program in Integrated Microbial Biodiversity, Toronto, Canada
| | - Steven G. Ball
- Université des Sciences et Technologies de Lille, Unité de Glycobiologie Structurale et Fonctionnelle, UMR8576 CNRS-USTL, Cité Scientifique, Villeneuve d’Ascq Cedex, France
| | - Joel B. Dacks
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - C. Graham Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Andrew J. Roger
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
- Canadian Institute for Advanced Research, CIFAR Program in Integrated Microbial Biodiversity, Toronto, Canada
| |
Collapse
|
8
|
Eme L, Gentekaki E, Curtis B, Archibald JM, Roger AJ. Lateral Gene Transfer in the Adaptation of the Anaerobic Parasite Blastocystis to the Gut. Curr Biol 2017; 27:807-820. [PMID: 28262486 DOI: 10.1016/j.cub.2017.02.003] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 01/26/2017] [Accepted: 02/01/2017] [Indexed: 12/22/2022]
Abstract
Blastocystis spp. are the most prevalent eukaryotic microbes found in the intestinal tract of humans. Here we present an in-depth investigation of lateral gene transfer (LGT) in the genome of Blastocystis sp. subtype 1. Using rigorous phylogeny-based methods and strict validation criteria, we show that ∼2.5% of the genes of this organism were recently acquired by LGT. We identify LGTs both from prokaryote and eukaryote donors. Several transfers occurred specifically in ancestors of a subset of Blastocystis subtypes, demonstrating that LGT is an ongoing process. Functional predictions reveal that these genes are involved in diverse metabolic pathways, many of which appear related to adaptation of Blastocystis to the gut environment. Specifically, we identify genes involved in carbohydrate scavenging and metabolism, anaerobic amino acid and nitrogen metabolism, oxygen-stress resistance, and pH homeostasis. A number of the transferred genes encoded secreted proteins that are potentially involved in infection, escaping host defense, or most likely affect the prokaryotic microbiome and the inflammation state of the gut. We also show that Blastocystis subtypes differ in the nature and copy number of LGTs that could relate to variation in their prevalence and virulence. Finally, we identified bacterial-derived genes encoding NH3-dependent nicotinamide adenine dinucleotide (NAD) synthase in Blastocystis and other protozoan parasites, which are promising targets for drug development. Collectively, our results suggest new avenues for research into the role of Blastocystis in intestinal disease and unequivocally demonstrate that LGT is an important mechanism by which eukaryotic microbes adapt to new environments.
Collapse
Affiliation(s)
- Laura Eme
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College Street, Halifax, NS B3H 4R2, Canada
| | - Eleni Gentekaki
- School of Science and Human Gut Microbiome for Health Research Unit, Mae Fah Luang University, Chiang Rai 57100, Thailand
| | - Bruce Curtis
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College Street, Halifax, NS B3H 4R2, Canada
| | - John M Archibald
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College Street, Halifax, NS B3H 4R2, Canada; Canadian Institute for Advanced Research, Program in Integrated Microbial Biodiversity, 180 Dundas Street W., Toronto, ON M5G 1Z8, Canada
| | - Andrew J Roger
- Centre for Comparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College Street, Halifax, NS B3H 4R2, Canada; Canadian Institute for Advanced Research, Program in Integrated Microbial Biodiversity, 180 Dundas Street W., Toronto, ON M5G 1Z8, Canada.
| |
Collapse
|
9
|
Stensvold CR, Clark CG. Current status of Blastocystis: A personal view. Parasitol Int 2016; 65:763-771. [PMID: 27247124 DOI: 10.1016/j.parint.2016.05.015] [Citation(s) in RCA: 216] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 05/10/2016] [Accepted: 05/27/2016] [Indexed: 12/15/2022]
Abstract
Despite Blastocystis being one of the most widespread and prevalent intestinal eukaryotes, its role in health and disease remains elusive. DNA-based detection methods have led to a recognition that the organism is much more common than previously thought, at least in some geographic regions and some groups of individuals. Molecular methods have also enabled us to start categorizing the vast genetic heterogeneity that exists among Blastocystis isolates, wherein the key to potential differences in the clinical outcome of Blastocystis carriage may lie. In this review we summarize some of the recent developments and advances in Blastocystis research, including updates on diagnostic methods, molecular epidemiology, genetic diversity, host specificity, clinical significance, taxonomy, and genomics. As we are now in the microbiome era, we also review some of the steps taken towards understanding the place of Blastocystis in the intestinal microbiota.
Collapse
Affiliation(s)
| | - C Graham Clark
- London School of Hygiene and Tropical Medicine, London, UK
| |
Collapse
|
10
|
Nagel R, Traub RJ, Kwan MMS, Bielefeldt-Ohmann H. Blastocystis specific serum immunoglobulin in patients with irritable bowel syndrome (IBS) versus healthy controls. Parasit Vectors 2015; 8:453. [PMID: 26373392 PMCID: PMC4572630 DOI: 10.1186/s13071-015-1069-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 09/03/2015] [Indexed: 12/14/2022] Open
Abstract
Background Blastocystis species are common enteric human parasites and carriage has been linked to Irritable Bowel Syndrome (IBS), particularly diarrhoea-predominant IBS. The spectrum of immune reactivity to Blastocystis proteins has been reported previously in symptomatic patients. We investigated differences in serum immunoglobulin profiles between patients with IBS, both positive and negative for Blastocystis carriage, and healthy controls (HC). Methods Forty diarrhoea-predominant IBS patients (26 patients positive for Blastocystis sp., 14 negative patients) and forty HC (24 positive, 16 Blastocystis-negative) were enrolled. Age, gender, ethnicity and serum immunoglobulin A (IgA) levels were recorded and faecal specimens were analysed using smear, culture and polymerase chain reaction amplification of ribosomal DNA. Sera were tested in Western blots and the reactivities compared to known targets using monoclonal antibodies Blastofluor® (Blastocystis specific antibody), MAb1D5 (cytopathicto Blastocystis cells), anti-promatrix metalloprotease-9 (anti-MMP-9) and SDS-PAGE zymograms. Results Levels of serum IgA were significantly lower in Blastocystis carriers (p < 0.001) but had no relationship to symptoms. Western blots demonstrated serum IgG antibodies specific for Blastocystis proteins of 17,27,37,50,60-65, 75–90, 95–105 and 150 kDa MW. Reactivity to the 27, 50 and 75-95 kDa proteins were found more frequently in the IBS group compared to the HC’s (p < 0.001) and correlation was greater for Blastocystis-positive IBS patients (p < 0.001) than for negative IBS patients (p < 0.05). MAb1D5 reacted with proteins of 27 and 100 kDa, and anti-MMP-9 with 27, 50 and 75-100 kDa proteins. Bands were seen in zymograms around 100 kDa. Conclusions Low serum IgA levels are associated with Blastocystis carriage. All IBS patients were more likely to demonstrate reactivity with Blastocystis proteins of 27 kDa (likely a cysteine protease), 50 and 75-95 kDa MW compared to HC. The presence of antibodies to these Blastocystis proteins in some Blastocystis-negative subjects suggests either prior exposure to Blastocystis organisms or antibody cross reactivities. The anti-proMMP-9 reaction at 50 and 75–100 kDa and the zymogram result suggest that metalloproteases may be important Blastocystis antigens. Trial registration Australian and New Zealand Clinical Trials registry ACTRN: 12611000918921 Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1069-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Robyn Nagel
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD, 4343, Australia. .,Toowoomba Gastroenterology Clinic, Suite 105 Medici Medical Centre, 15 Scott St, Toowoomba, QLD, 4350, Australia.
| | - Rebecca J Traub
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD, 4343, Australia. .,Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Marcella M S Kwan
- Rural Clinical School, School of Medicine, The University of Queensland, Toowoomba, 4350, Australia.
| | - Helle Bielefeldt-Ohmann
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD, 4343, Australia. .,Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, QLD, 4072, Australia.
| |
Collapse
|
11
|
Venton D. Highlight: Not Like a Textbook--Nuclear Genes in Blastocystis Use mRNA Polyadenylation for Stop Codons. Genome Biol Evol 2014; 6:1962-3. [PMID: 25104295 PMCID: PMC4159010 DOI: 10.1093/gbe/evu167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|