uu.seUppsala University Publications
Change search
Link to record
Permanent link

Direct link
BETA
Andersson, Jan O.
Alternative names
Publications (10 of 47) Show all publications
Leger, M. M., Kolisko, M., Kamikawa, R., Stairs, C. W., Kume, K., Cepicka, I., . . . Roger, A. J. (2017). Organelles that illuminate the origins of Trichomonas hydrogenosomes and Giardia mitosomes. NATURE ECOLOGY & EVOLUTION, 1(4), Article ID UNSP 0092.
Open this publication in new window or tab >>Organelles that illuminate the origins of Trichomonas hydrogenosomes and Giardia mitosomes
Show others...
2017 (English)In: NATURE ECOLOGY & EVOLUTION, ISSN 2397-334X, Vol. 1, no 4, article id UNSP 0092Article in journal (Refereed) Published
Abstract [en]

Many anaerobic microbial parasites possess highly modified mitochondria known as mitochondrion-related organelles (MROs). The best-studied of these are the hydrogenosomes of Trichomonas vaginalis and Spironucleus salmonicida, which produce ATP anaerobically through substrate-level phosphorylation with concomitant hydrogen production; and the mitosomes of Giardia intestinalis, which are functionally reduced and lack any role in ATP production. Howewer, to understand the metabolic specializations that these MROs underwent in adaptation to parasitism, data from their free-living relatives are needed. Here, we present a large-scale comparative transcriptomic study of MROs across a major eukaryotic group, Metamonada, examining lineage-specific gain and loss of metabolic functions in the MROs of Trichomonas, Giardia, Spironucleus and their free-living relatives. Our analyses uncover a complex history of ATP production machinery in diplomonads such as Giardia, and their closest relative, Dysnectes; and a correlation between the glycine cleavage machinery and lifestyles. Our data further suggest the existence of a previously undescribed biochemical class of MRO that generates hydrogen but is incapable of ATP synthesis.

National Category
Microbiology Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-344540 (URN)10.1038/s41559-017-0092 (DOI)000417171500014 ()28474007 (PubMedID)
Available from: 2018-03-07 Created: 2018-03-07 Last updated: 2018-08-21Bibliographically approved
Einarsson, E., Ástvaldsson, Á., Hultenby, K., Andersson, J. O., Svärd, S. G. & Jerlstrom-Hultqvist, J. (2016). Comparative cell biology and evolution of Annexins in Diplomonads. MSphere, 1(2), Article ID e00032-15.
Open this publication in new window or tab >>Comparative cell biology and evolution of Annexins in Diplomonads
Show others...
2016 (English)In: MSphere, ISSN 2379-5042, Vol. 1, no 2, article id e00032-15Article in journal (Refereed) Published
Abstract [en]

Annexins are multifunctional, calcium-binding proteins found in organisms across all kingdoms. Most studies of annexins from single-celled eukaryotes have focused on the alpha-giardins, proteins assigned to the group E annexins, expressed by the diplomonad Giardia intestinalis. We have characterized the annexin gene family in another diplomonad parasite, Spironucleus salmonicida, by phylogenetic and experimental approaches. We constructed a comprehensive phylogeny of the diplomonad group E annexins and found that they are abundant across the group with frequent gene duplications and losses. The annexins of S. salmonicida were found to be related to alpha-giardins but with better-preserved type II Ca2+ coordination sites. Two annexins were confirmed to bind phospholipids in a Ca2+-dependent fashion but with different specificities. Superresolution and confocal microscopy of epitope-tagged S. salmonicida annexins revealed localization to distinct parts of the cytoskeleton and membrane. The ultrastructural details of the localization of several annexins were determined by proximity labeling and transmission electron microscopy. Two annexins localize to a novel cytoskeletal structure in the anterior of the cell. Our results show that the annexin gene family is expanded in diplomonads and that these group E annexins are associated mostly with cytoskeletal and membrane structures. IMPORTANCE Annexins are proteins that associate with phospholipids in a Ca2+-dependent fashion. These proteins have been intensely studied in animals and plants because of their importance in diverse cellular processes, yet very little is known about annexins in single-celled eukaryotes, which represent the largest diversity of organisms. The human intestinal parasite Giardia intestinalis is known to have more annexins than humans, and they contribute to its pathogenic potential. In this study, we investigated the annexin complement in the salmon pathogen Spironucleus salmonicida, a relative of G. intestinalis. We found that S. salmonicida has a large repertoire of annexins and that the gene family has expanded separately across diplomonads, with members showing sequence diversity similar to that seen across kingdom-level groups such as plants and animals. S. salmonicida annexins are prominent components of the cytoskeleton and membrane. Two annexins are associated with a previously unrecognized structure in the anterior of the cell.

Place, publisher, year, edition, pages
Uppsala: , 2016
Keywords
intestinal parasite, annexins, diplomonad, Spironucleus salmonicida, Giardia, proximity labeling, APEX
National Category
Cell Biology Microbiology Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-264537 (URN)10.1128/mSphere.00032-15 (DOI)000392584700008 ()
Funder
Swedish Research Council, 2012-3364Swedish Research Council Formas, 2013-910
Available from: 2015-10-14 Created: 2015-10-14 Last updated: 2019-03-19Bibliographically approved
Ankarklev, J., Franzen, O., Peirasmaki, D., Jerlstrom-Hultqvist, J., Lebbad, M., Andersson, J., . . . Svärd, S. G. (2015). Comparative genomic analyses of freshly isolated Giardia intestinalis assemblage A isolates. BMC Genomics, 16, Article ID 697.
Open this publication in new window or tab >>Comparative genomic analyses of freshly isolated Giardia intestinalis assemblage A isolates
Show others...
2015 (English)In: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 16, article id 697Article in journal (Refereed) Published
Abstract [en]

Background: The diarrhea-causing protozoan Giardia intestinalis makes up a species complex of eight different assemblages (A-H), where assemblage A and B infect humans. Comparative whole-genome analyses of three of these assemblages have shown that there is significant divergence at the inter-assemblage level, however little is currently known regarding variation at the intra-assemblage level. We have performed whole genome sequencing of two sub-assemblage AII isolates, recently axenized from symptomatic human patients, to study the biological and genetic diversity within assemblage A isolates. Results: Several biological differences between the new and earlier characterized assemblage A isolates were identified, including a difference in growth medium preference. The two AII isolates were of different sub-assemblage types (AII-1 [AS175] and AII-2 [AS98]) and showed size differences in the smallest chromosomes. The amount of genetic diversity was characterized in relation to the genome of the Giardia reference isolate WB, an assemblage AI isolate. Our analyses indicate that the divergence between AI and AII is approximately 1 %, represented by similar to 100,000 single nucleotide polymorphisms (SNP) distributed over the chromosomes with enrichment in variable genomic regions containing surface antigens. The level of allelic sequence heterozygosity (ASH) in the two AII isolates was found to be 0.25-0.35 %, which is 25-30 fold higher than in the WB isolate and 10 fold higher than the assemblage AII isolate DH (0.037 %). 35 protein-encoding genes, not found in the WB genome, were identified in the two AII genomes. The large gene families of variant-specific surface proteins (VSPs) and high cysteine membrane proteins (HCMPs) showed isolate-specific divergences of the gene repertoires. Certain genes, often in small gene families with 2 to 8 members, localize to the variable regions of the genomes and show high sequence diversity between the assemblage A isolates. One of the families, Bactericidal/ Permeability Increasing-like protein (BPIL), with eight members was characterized further and the proteins were shown to localize to the ER in trophozoites. Conclusions: Giardia genomes are modular with highly conserved core regions mixed up by variable regions containing high levels of ASH, SNPs and variable surface antigens. There are significant genomic variations in assemblage A isolates, in terms of chromosome size, gene content, surface protein repertoire and gene polymorphisms and these differences mainly localize to the variable regions of the genomes. The large genetic differences within one assemblage of G. intestinalis strengthen the argument that the assemblages represent different Giardia species.

National Category
Genetics Microbiology
Identifiers
urn:nbn:se:uu:diva-264039 (URN)10.1186/s12864-015-1893-6 (DOI)000361093400009 ()26370391 (PubMedID)
Funder
Swedish Research Council FormasSwedish Research Council
Available from: 2015-10-06 Created: 2015-10-05 Last updated: 2019-04-19Bibliographically approved
Xu, F., Jerlström-Hultqvist, J., Einarsson, E., Astvaldsson, A., Svärd, S. G. & Andersson, J. O. (2014). The genome of Spironucleus salmonicida highlights a fish pathogen adapted to fluctuating environments. PLoS Genetics, 10(2), e1004053
Open this publication in new window or tab >>The genome of Spironucleus salmonicida highlights a fish pathogen adapted to fluctuating environments
Show others...
2014 (English)In: PLoS Genetics, ISSN 1553-7390, E-ISSN 1553-7404, Vol. 10, no 2, p. e1004053-Article in journal (Refereed) Published
Abstract [en]

Spironucleus salmonicida causes systemic infections in salmonid fish. It belongs to the group diplomonads, binucleated heterotrophic flagellates adapted to micro-aerobic environments. Recently we identified energy-producing hydrogenosomes in S. salmonicida. Here we present a genome analysis of the fish parasite with a focus on the comparison to the more studied diplomonad Giardia intestinalis. We annotated 8067 protein coding genes in the ∼12.9 Mbp S. salmonicida genome. Unlike G. intestinalis, promoter-like motifs were found upstream of genes which are correlated with gene expression, suggesting a more elaborate transcriptional regulation. S. salmonicida can utilise more carbohydrates as energy sources, has an extended amino acid and sulfur metabolism, and more enzymes involved in scavenging of reactive oxygen species compared to G. intestinalis. Both genomes have large families of cysteine-rich membrane proteins. A cluster analysis indicated large divergence of these families in the two diplomonads. Nevertheless, one of S. salmonicida cysteine-rich proteins was localised to the plasma membrane similar to G. intestinalis variant-surface proteins. We identified S. salmonicida homologs to cyst wall proteins and showed that one of these is functional when expressed in Giardia. This suggests that the fish parasite is transmitted as a cyst between hosts. The extended metabolic repertoire and more extensive gene regulation compared to G. intestinalis suggest that the fish parasite is more adapted to cope with environmental fluctuations. Our genome analyses indicate that S. salmonicida is a well-adapted pathogen that can colonize different sites in the host.

National Category
Microbiology Genetics
Identifiers
urn:nbn:se:uu:diva-224545 (URN)10.1371/journal.pgen.1004053 (DOI)000332021500041 ()24516394 (PubMedID)
Available from: 2014-05-14 Created: 2014-05-14 Last updated: 2019-03-19Bibliographically approved
Andersson, J. O. (2013). Gene Transfer and the Chimeric Nature of Eukaryotic Genomes. In: Uri Gophna (Ed.), Lateral Gene Transfer in Evolution: (pp. 181-197). New York: Springer Science+Business Media B.V.
Open this publication in new window or tab >>Gene Transfer and the Chimeric Nature of Eukaryotic Genomes
2013 (English)In: Lateral Gene Transfer in Evolution / [ed] Uri Gophna, New York: Springer Science+Business Media B.V., 2013, p. 181-197Chapter in book (Other academic)
Place, publisher, year, edition, pages
New York: Springer Science+Business Media B.V., 2013
National Category
Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-224550 (URN)978-1-4614-7779-2 (ISBN)
Available from: 2014-05-14 Created: 2014-05-14 Last updated: 2014-05-14
Jerlström-Hultqvist, J., Einarsson, E., Xu, F., Hjort, K., Ek, B., Steinhauf, D., . . . Svärd, S. G. (2013). Hydrogenosomes in the diplomonad Spironucleus salmonicida. Nature Communications, 4, 2493
Open this publication in new window or tab >>Hydrogenosomes in the diplomonad Spironucleus salmonicida
Show others...
2013 (English)In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 4, p. 2493-Article in journal (Refereed) Published
Abstract [en]

Acquisition of the mitochondrion is a key event in the evolution of the eukaryotic cell, but diversification of the organelle has occurred during eukaryotic evolution. One example of such mitochondria-related organelles (MROs) are hydrogenosomes, which produce ATP by substrate- level phosphorylation with hydrogen as a byproduct. The diplomonad parasite Giardia intestinalis harbours mitosomes, another type of MRO. Here we identify MROs in the salmon parasite Spironucleus salmonicida with similar protein import and Fe-S cluster assembly machineries as in Giardia mitosomes. We find that hydrogen production is prevalent in the diplomonad genus Spironucleus, and that S. salmonicida MROs contain enzymes characteristic of hydrogenosomes. Evolutionary analyses of known hydrogenosomal components indicate their presence in the diplomonad ancestor, and subsequent loss in Giardia. Our results suggest that hydrogenosomes are metabolic adaptations predating the split between parabasalids and diplomonads, which is deeper than the split between animals and fungi in the eukaryotic tree.

National Category
Natural Sciences
Identifiers
urn:nbn:se:uu:diva-210741 (URN)10.1038/ncomms3493 (DOI)000325534300002 ()
Available from: 2013-11-14 Created: 2013-11-14 Last updated: 2017-12-06Bibliographically approved
Ankarklev, J., Hestvik, E., Lebbad, M., Lindh, J., Kaddu-Mulindwa, D. H., Andersson, J. O., . . . Svärd, S. G. (2012). Common Coinfections of Giardia intestinalis and Helicobacter pylori in Non-Symptomatic Ugandan Children. PLOS Neglected Tropical Diseases, 6(8), e1780
Open this publication in new window or tab >>Common Coinfections of Giardia intestinalis and Helicobacter pylori in Non-Symptomatic Ugandan Children
Show others...
2012 (English)In: PLOS Neglected Tropical Diseases, ISSN 1935-2735, Vol. 6, no 8, p. e1780-Article in journal (Refereed) Published
Abstract [en]

Background: The protozoan parasite Giardia intestinalis and the pathogenic bacterium Helicobacter pylori are well known for their high prevalences in human hosts worldwide. The prevalence of both organisms is known to peak in densely populated, low resource settings and children are infected early in life. Different Giardia genotypes/assemblages have been associated with different symptoms and H. pylori with induction of cancer. Despite this, not much data are available from sub-Saharan Africa with regards to the prevalence of different G. intestinalis assemblages and their potential association with H. pylori infections.

Methodology/Principal Findings: Fecal samples from 427 apparently healthy children, 0-12 years of age, living in urban Kampala, Uganda were analyzed for the presence of H. pylori and G. intestinalis. G. intestinalis was found in 86 (20.1%) out of the children and children age 1<5 years had the highest rates of colonization. H. pylori was found in 189 (44.3%) out of the 427 children and there was a 3-fold higher risk of concomitant G. intestinalis and H. pylori infections compared to non-concomitant G. intestinalis infection, OR = 2.9 (1.7-4.8). No significant association was found in the studied population with regard to the presence of Giardia and gender, type of toilet, source of drinking water or type of housing. A panel of 45 G. intestinalis positive samples was further analyzed using multi-locus genotyping (MLG) on three loci, combined with assemblage-specific analyses. Giardia MLG analysis yielded a total of five assemblage AII, 25 assemblage B, and four mixed assemblage infections. The assemblage B isolates were highly genetically variable but no significant association was found between Giardia assemblage type and H. pylori infection.

Conclusions/Significance: This study shows that Giardia assemblage B dominates in children in Kampala, Uganda and that the presence of H. pylori is an associated risk factor for G. intestinalis infection.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-182779 (URN)10.1371/journal.pntd.0001780 (DOI)000308497100020 ()
Available from: 2012-10-16 Created: 2012-10-15 Last updated: 2012-10-16Bibliographically approved
Andersson, J. O. (2012). Double peaks reveal rare diplomonad sex. Trends in Parasitology, 28(2), 46-52
Open this publication in new window or tab >>Double peaks reveal rare diplomonad sex
2012 (English)In: Trends in Parasitology, ISSN 1471-4922, E-ISSN 1471-5007, Vol. 28, no 2, p. 46-52Article in journal (Refereed) Published
Abstract [en]

Diplomonads, single-celled eukaryotes, are unusual in having two nuclei. Each nucleus contains two copies of the genome and is transcriptionally active. It has long been assumed that diplomonads in general and Giardia intestinalis in particular are asexual. Genomic and population genetic data now challenge that assumption and extensive allelic sequence heterogeneity has been reported in some but not all examined diplomonad lineages. Here it is argued, in contrast to common assumptions, that allelic differences indicate recent sexual events, and isolates that have divided asexually for many generations have lost their allelic variation owing to within-cell recombination. Consequently, directed studies of the allelic sequence heterogeneity in diverse diplomonad lineages are likely to reveal details about the enigmatic diplomonad sexual life cycle.

National Category
Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-166665 (URN)10.1016/j.pt.2011.11.002 (DOI)000300761600002 ()22192817 (PubMedID)
Available from: 2012-01-12 Created: 2012-01-12 Last updated: 2017-12-08Bibliographically approved
Xu, F., Jerlström-Hultqvist, J. & Andersson, J. O. (2012). Genome-Wide Analyses of Recombination Suggest That Giardia intestinalis Assemblages Represent Different Species. Molecular biology and evolution, 29(10), 2895-2898
Open this publication in new window or tab >>Genome-Wide Analyses of Recombination Suggest That Giardia intestinalis Assemblages Represent Different Species
2012 (English)In: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 29, no 10, p. 2895-2898Article in journal (Refereed) Published
Abstract [en]

Giardia intestinalis is a major cause of waterborne enteric disease in humans. The species is divided into eight assemblages suggested to represent separate Giardia species based on host specificities and the genetic divergence of marker genes. We have investigated whether genome-wide recombination occurs between assemblages using the three available G. intestinalis genomes. First, the relative nonsynonymous substitution rates of the homologs were compared for 4,009 positional homologs. The vast majority of these comparisons indicate genetic isolation without interassemblage recombinations. Only a region of 6 kbp suggests genetic exchange between assemblages A and E, followed by gene conversion events. Second, recombination-detecting software fails to identify within-gene recombination between the different assemblages for most of the homologs. Our results indicate very low frequency of recombination between the syntenic core genes, suggesting that G. intestinalis assemblages are genetically isolated lineages and thus should be viewed as separated Giardia species.

National Category
Natural Sciences Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-175947 (URN)10.1093/molbev/mss107 (DOI)000309927900003 ()22474166 (PubMedID)
Available from: 2012-06-14 Created: 2012-06-14 Last updated: 2017-12-07Bibliographically approved
Andersson, J. O. (2012). Phylogenomic approaches underestimate eukaryotic gene transfer. Mobile Genetic Elements, 2(1), 59-62
Open this publication in new window or tab >>Phylogenomic approaches underestimate eukaryotic gene transfer
2012 (English)In: Mobile Genetic Elements, Vol. 2, no 1, p. 59-62Article in journal (Refereed) Published
Abstract [en]

Phylogenomic approaches have shown that eukaryotes acquire genes via gene transfer. However, there are two fundamental problems for most of these analyses; only transfers from prokaryotes are analyzed and the screening procedures applied assume that gene transfer is rare for eukaryotes. Directed studies of the impact of gene transfer on diverse eukaryotic lineages produce a much more complex picture. Many gene families are affected by multiple transfer events from prokaryotes to eukaryotes, and transfers between eukaryotic lineages are routinely detected. This suggests that the assumptions applied in traditional phylogenomic approaches are too naïve and result in many false negatives. This issue was recently addressed by identifying and analyzing the evolutionary history of 49 patchily distributed proteins shared between Dictyostelium and bacteria. The vast majority of these gene families showed strong indications of gene transfers, both between and within the three domains of life. However, only one of these was previously reported as a gene transfer candidate using a traditional phylogenomic approach. This clearly illustrates that more realistic assumptions are urgently needed in genome-wide studies of eukaryotic gene transfer.

National Category
Evolutionary Biology
Identifiers
urn:nbn:se:uu:diva-224548 (URN)10.4161/mge.19668 (DOI)
Available from: 2014-05-14 Created: 2014-05-14 Last updated: 2014-05-14Bibliographically approved
Organisations

Search in DiVA

Show all publications