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1.
Plant J ; 99(4): 589-609, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31111606

RESUMEN

Carbohydrate-active enzymes (CAZymes) catalyze the formation and modification of glycoproteins, glycolipids, starch, secondary metabolites and cell wall biopolymers. They are key enzymes for the biosynthesis of food and renewable biomass. Woody biomass is particularly important for long-term carbon storage and as an abundant renewable natural resource for many industrial applications. This study presents a re-annotation of CAZyme genes in the current Populus trichocarpa genome assembly and in silico functional characterization, based on high-resolution RNA-Seq data sets. Altogether, 1914 CAZyme and expansin genes were annotated in 101 families. About 1797 of these genes were found expressed in at least one Populus organ. We identified genes involved in the biosynthesis of different cell wall polymers and their paralogs. Whereas similar families exist in poplar and Arabidopsis thaliana (with the exception of CBM13 found only in poplar), a few families had significantly different copy numbers between the two species. To identify the transcriptional coordination and functional relatedness within the CAZymes and other proteins, we performed co-expression network analysis of CAZymes in wood-forming tissues using the AspWood database (http://aspwood.popgenie.org/aspwood-v3.0/) for Populus tremula. This provided an overview of the transcriptional changes in CAZymes during the transition from primary to secondary wall formation, and the clustering of transcripts into potential regulons. Candidate enzymes involved in the biosynthesis of polysaccharides were identified along with many tissue-specific uncharacterized genes and transcription factors. These collections offer a rich source of targets for the modification of secondary cell wall biosynthesis and other developmental processes in woody plants.


Asunto(s)
Proteínas de Plantas/metabolismo , Populus/genética , Populus/metabolismo , Madera/metabolismo , Pared Celular/genética , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Genómica , Proteínas de Plantas/genética , Secuenciación Completa del Genoma , Madera/genética
2.
Mol Biol Evol ; 35(11): 2786-2804, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30239843

RESUMEN

Fungi are evolutionary shape shifters and adapt quickly to new environments. Ectomycorrhizal (EM) symbioses are mutualistic associations between fungi and plants and have evolved repeatedly and independently across the fungal tree of life, suggesting lineages frequently reconfigure genome content to take advantage of open ecological niches. To date analyses of genomic mechanisms facilitating EM symbioses have involved comparisons of distantly related species, but here, we use the genomes of three EM and two asymbiotic (AS) fungi from the genus Amanita as well as an AS outgroup to study genome evolution following a single origin of symbiosis. Our aim was to identify the defining features of EM genomes, but our analyses suggest no clear differentiation of genome size, gene repertoire size, or transposable element content between EM and AS species. Phylogenetic inference of gene gains and losses suggests the transition to symbiosis was dominated by the loss of plant cell wall decomposition genes, a confirmation of previous findings. However, the same dynamic defines the AS species A. inopinata, suggesting loss is not strictly associated with origin of symbiosis. Gene expansions in the common ancestor of EM Amanita were modest, but lineage specific and large gene family expansions are found in two of the three EM extant species. Even closely related EM genomes appear to share few common features. The genetic toolkit required for symbiosis appears already encoded in the genomes of saprotrophic species, and this dynamic may explain the pervasive, recurrent evolution of ectomycorrhizal associations.


Asunto(s)
Amanita/genética , Evolución Biológica , Genoma Fúngico , Micorrizas/fisiología , Adaptación Biológica , Amanita/enzimología , Filogenia , Simbiosis
3.
Mol Biol Evol ; 35(8): 1840-1854, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29771364

RESUMEN

Ustilaginomycotina is home to a broad array of fungi including important plant pathogens collectively called smut fungi. Smuts are biotrophs that produce characteristic perennating propagules called teliospores, one of which, Ustilago maydis, is a model genetic organism. Broad exploration of smut biology has been hampered by limited phylogenetic resolution of Ustilaginiomycotina as well as an overall lack of genomic data for members of this subphylum. In this study, we sequenced eight Ustilaginomycotina genomes from previously unrepresented lineages, deciphered ordinal-level phylogenetic relationships for the subphylum, and performed comparative analyses. Unlike other Basidiomycota subphyla, all sampled Ustilaginomycotina genomes are relatively small and compact. Ancestral state reconstruction analyses indicate that teliospore formation was present at the origin of the subphylum. Divergence time estimation dates the divergence of most extant smut fungi after that of grasses (Poaceae). However, we found limited conservation of well-characterized genes related to smut pathogenesis from U. maydis, indicating dissimilar pathogenic mechanisms exist across other smut lineages. The genomes of Malasseziomycetes are highly diverged from the other sampled Ustilaginomycotina, likely due to their unique history as mammal-associated lipophilic yeasts. Despite extensive genomic data, the phylogenetic placement of this class remains ambiguous. Although the sampled Ustilaginomycotina members lack many core enzymes for plant cell wall decomposition and starch catabolism, we identified several novel carbohydrate active enzymes potentially related to pectin breakdown. Finally, ∼50% of Ustilaginomycotina species-specific genes are present in previously undersampled and rare lineages, highlighting the importance of exploring fungal diversity as a resource for novel gene discovery.


Asunto(s)
Interacciones Huésped-Patógeno/genética , Filogenia , Ustilaginales/genética , Genoma Fúngico , Enfermedades de las Plantas , Ustilaginales/clasificación , Ustilaginales/enzimología , Ustilaginales/patogenicidad , Secuenciación Completa del Genoma
4.
Fungal Genet Biol ; 112: 40-46, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28803908

RESUMEN

Basidiomycete fungi can degrade a wide range of plant biomass, including living and dead trees, forest litter, crops, and plant matter in soils. Understanding the process of plant biomass decay by basidiomycetes could facilitate their application in various industrial sectors such as food & feed, detergents and biofuels, and also provide new insights into their essential biological role in the global carbon cycle. The fast expansion of basidiomycete genomic and functional genomics data (e.g. transcriptomics, proteomics) has facilitated exploration of key genes and regulatory mechanisms of plant biomass degradation. In this study, we comparatively analyzed 22 transcriptome datasets from basidiomycetes related to plant biomass degradation, and identified 328 commonly induced genes and 318 repressed genes, and defined a core set of carbohydrate active enzymes (CAZymes), which was shared by most of the basidiomycete species. High conservation of these CAZymes in genomes and similar regulation pattern in transcriptomics data from lignocellulosic substrates indicate their key role in plant biomass degradation and need for their further biochemical investigation.


Asunto(s)
Basidiomycota/enzimología , Basidiomycota/genética , Hidrolasas/biosíntesis , Hidrolasas/genética , Lignina/metabolismo , Plantas/metabolismo , Transcriptoma , Basidiomycota/metabolismo , Biomasa
5.
New Phytol ; 220(4): 1161-1171, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29355972

RESUMEN

Arbuscular mycorrhizal fungi (AMF) are known to improve plant fitness through the establishment of mycorrhizal symbioses. Genetic and phenotypic variations among closely related AMF isolates can significantly affect plant growth, but the genomic changes underlying this variability are unclear. To address this issue, we improved the genome assembly and gene annotation of the model strain Rhizophagus irregularis DAOM197198, and compared its gene content with five isolates of R. irregularis sampled in the same field. All isolates harbor striking genome variations, with large numbers of isolate-specific genes, gene family expansions, and evidence of interisolate genetic exchange. The observed variability affects all gene ontology terms and PFAM protein domains, as well as putative mycorrhiza-induced small secreted effector-like proteins and other symbiosis differentially expressed genes. High variability is also found in active transposable elements. Overall, these findings indicate a substantial divergence in the functioning capacity of isolates harvested from the same field, and thus their genetic potential for adaptation to biotic and abiotic changes. Our data also provide a first glimpse into the genome diversity that resides within natural populations of these symbionts, and open avenues for future analyses of plant-AMF interactions that link AMF genome variation with plant phenotype and fitness.


Asunto(s)
Variación Genética , Genoma Fúngico , Glomeromycota/genética , Modelos Biológicos , Micorrizas/genética , Simbiosis/genética , Adaptación Fisiológica/genética , Elementos Transponibles de ADN/genética , Proteínas Fúngicas/química , Genes Fúngicos , Glomeromycota/aislamiento & purificación , Anotación de Secuencia Molecular , Filogenia , Dominios Proteicos , Especificidad de la Especie
6.
New Phytol ; 217(3): 1213-1229, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29315638

RESUMEN

Some soil fungi in the Leotiomycetes form ericoid mycorrhizal (ERM) symbioses with Ericaceae. In the harsh habitats in which they occur, ERM plant survival relies on nutrient mobilization from soil organic matter (SOM) by their fungal partners. The characterization of the fungal genetic machinery underpinning both the symbiotic lifestyle and SOM degradation is needed to understand ERM symbiosis functioning and evolution, and its impact on soil carbon (C) turnover. We sequenced the genomes of the ERM fungi Meliniomyces bicolor, M. variabilis, Oidiodendron maius and Rhizoscyphus ericae, and compared their gene repertoires with those of fungi with different lifestyles (ecto- and orchid mycorrhiza, endophytes, saprotrophs, pathogens). We also identified fungal transcripts induced in symbiosis. The ERM fungal gene contents for polysaccharide-degrading enzymes, lipases, proteases and enzymes involved in secondary metabolism are closer to those of saprotrophs and pathogens than to those of ectomycorrhizal symbionts. The fungal genes most highly upregulated in symbiosis are those coding for fungal and plant cell wall-degrading enzymes (CWDEs), lipases, proteases, transporters and mycorrhiza-induced small secreted proteins (MiSSPs). The ERM fungal gene repertoire reveals a capacity for a dual saprotrophic and biotrophic lifestyle. This may reflect an incomplete transition from saprotrophy to the mycorrhizal habit, or a versatile life strategy similar to fungal endophytes.


Asunto(s)
Genómica , Micorrizas/genética , Plantas/microbiología , Simbiosis/genética , Transcriptoma/genética , Secuencia Conservada/genética , Hongos/clasificación , Hongos/genética , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Filogenia , Metabolismo Secundario/genética , Especificidad por Sustrato , Regulación hacia Arriba/genética
7.
BMC Genomics ; 18(1): 667, 2017 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-28851275

RESUMEN

BACKGROUND: The ascomycete fungus Colletotrichum higginsianum causes anthracnose disease of brassica crops and the model plant Arabidopsis thaliana. Previous versions of the genome sequence were highly fragmented, causing errors in the prediction of protein-coding genes and preventing the analysis of repetitive sequences and genome architecture. RESULTS: Here, we re-sequenced the genome using single-molecule real-time (SMRT) sequencing technology and, in combination with optical map data, this provided a gapless assembly of all twelve chromosomes except for the ribosomal DNA repeat cluster on chromosome 7. The more accurate gene annotation made possible by this new assembly revealed a large repertoire of secondary metabolism (SM) key genes (89) and putative biosynthetic pathways (77 SM gene clusters). The two mini-chromosomes differed from the ten core chromosomes in being repeat- and AT-rich and gene-poor but were significantly enriched with genes encoding putative secreted effector proteins. Transposable elements (TEs) were found to occupy 7% of the genome by length. Certain TE families showed a statistically significant association with effector genes and SM cluster genes and were transcriptionally active at particular stages of fungal development. All 24 subtelomeres were found to contain one of three highly-conserved repeat elements which, by providing sites for homologous recombination, were probably instrumental in four segmental duplications. CONCLUSION: The gapless genome of C. higginsianum provides access to repeat-rich regions that were previously poorly assembled, notably the mini-chromosomes and subtelomeres, and allowed prediction of the complete SM gene repertoire. It also provides insights into the potential role of TEs in gene and genome evolution and host adaptation in this asexual pathogen.


Asunto(s)
Cromosomas Fúngicos/genética , Colletotrichum/genética , Colletotrichum/metabolismo , Elementos Transponibles de ADN/genética , Genómica , Familia de Multigenes/genética , Recombinación Homóloga/genética , Anotación de Secuencia Molecular , Filogenia , Mutación Puntual/genética
8.
BMC Genomics ; 17(1): 1015, 2016 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-27938347

RESUMEN

BACKGROUND: Whereas an increasing number of pathogenic and mutualistic ascomycetous species were sequenced in the past decade, species showing a seemingly neutral association such as root endophytes received less attention. In the present study, the genome of Phialocephala subalpina, the most frequent species of the Phialocephala fortinii s.l. - Acephala applanata species complex, was sequenced for insight in the genome structure and gene inventory of these wide-spread root endophytes. RESULTS: The genome of P. subalpina was sequenced using Roche/454 GS FLX technology and a whole genome shotgun strategy. The assembly resulted in 205 scaffolds and a genome size of 69.7 Mb. The expanded genome size in P. subalpina was not due to the proliferation of transposable elements or other repeats, as is the case with other ascomycetous genomes. Instead, P. subalpina revealed an expanded gene inventory that includes 20,173 gene models. Comparative genome analysis of P. subalpina with 13 ascomycetes shows that P. subalpina uses a versatile gene inventory including genes specific for pathogens and saprophytes. Moreover, the gene inventory for carbohydrate active enzymes (CAZymes) was expanded including genes involved in degradation of biopolymers, such as pectin, hemicellulose, cellulose and lignin. CONCLUSIONS: The analysis of a globally distributed root endophyte allowed detailed insights in the gene inventory and genome organization of a yet largely neglected group of organisms. We showed that the ubiquitous root endophyte P. subalpina has a broad gene inventory that links pathogenic and saprophytic lifestyles.


Asunto(s)
Ascomicetos/genética , Endófitos/genética , Raíces de Plantas/microbiología , Ascomicetos/metabolismo , Ascomicetos/ultraestructura , Biología Computacional/métodos , Elementos Transponibles de ADN , Endófitos/metabolismo , Endófitos/ultraestructura , Ontología de Genes , Transferencia de Gen Horizontal , Genes Fúngicos , Genoma Fúngico , Genómica/métodos , Familia de Multigenes , Interferencia de ARN , Secuencias Repetitivas de Ácidos Nucleicos , Metabolismo Secundario/genética
9.
DNA Res ; 27(2)2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32531032

RESUMEN

White-rot (WR) fungi are pivotal decomposers of dead organic matter in forest ecosystems and typically use a large array of hydrolytic and oxidative enzymes to deconstruct lignocellulose. However, the extent of lignin and cellulose degradation may vary between species and wood type. Here, we combined comparative genomics, transcriptomics and secretome proteomics to identify conserved enzymatic signatures at the onset of wood-decaying activity within the Basidiomycota genus Pycnoporus. We observed a strong conservation in the genome structures and the repertoires of protein-coding genes across the four Pycnoporus species described to date, despite the species having distinct geographic distributions. We further analysed the early response of P. cinnabarinus, P. coccineus and P. sanguineus to diverse (ligno)-cellulosic substrates. We identified a conserved set of enzymes mobilized by the three species for breaking down cellulose, hemicellulose and pectin. The co-occurrence in the exo-proteomes of H2O2-producing enzymes with H2O2-consuming enzymes was a common feature of the three species, although each enzymatic partner displayed independent transcriptional regulation. Finally, cellobiose dehydrogenase-coding genes were systematically co-regulated with at least one AA9 lytic polysaccharide monooxygenase gene, indicative of enzymatic synergy in vivo. This study highlights a conserved core white-rot fungal enzymatic mechanism behind the wood-decaying process.


Asunto(s)
Deshidrogenasas de Carbohidratos/genética , Proteínas Fúngicas/genética , Lignina/genética , Pycnoporus/enzimología , Deshidrogenasas de Carbohidratos/metabolismo , Celulosa/metabolismo , Proteínas Fúngicas/metabolismo , Genoma Fúngico , Lignina/metabolismo , Filogenia , Pycnoporus/clasificación , Pycnoporus/genética , Madera/metabolismo , Madera/microbiología
10.
Genome Announc ; 6(14)2018 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-29622620

RESUMEN

Here, we report the genome sequence of wood-decaying white-rot fungus Phlebia centrifuga strain FBCC195, isolated from Norway spruce (Picea abies) in Finnish Lapland. The 34.66-Mb genome containing 13,785 gene models is similar to the genome length reported for other saprobic white-rot species.

11.
Biotechnol Biofuels ; 11: 201, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30061923

RESUMEN

BACKGROUND: Plant biomass conversion for green chemistry and bio-energy is a current challenge for a modern sustainable bioeconomy. The complex polyaromatic lignin polymers in raw biomass feedstocks (i.e., agriculture and forestry by-products) are major obstacles for biomass conversions. White-rot fungi are wood decayers able to degrade all polymers from lignocellulosic biomass including cellulose, hemicelluloses, and lignin. The white-rot fungus Polyporus brumalis efficiently breaks down lignin and is regarded as having a high potential for the initial treatment of plant biomass in its conversion to bio-energy. Here, we describe the extraordinary ability of P. brumalis for lignin degradation using its enzymatic arsenal to break down wheat straw, a lignocellulosic substrate that is considered as a biomass feedstock worldwide. RESULTS: We performed integrative multi-omics analyses by combining data from the fungal genome, transcriptomes, and secretomes. We found that the fungus possessed an unexpectedly large set of genes coding for Class II peroxidases involved in lignin degradation (19 genes) and GMC oxidoreductases/dehydrogenases involved in generating the hydrogen peroxide required for lignin peroxidase activity and promoting redox cycling of the fungal enzymes involved in oxidative cleavage of lignocellulose polymers (36 genes). The examination of interrelated multi-omics patterns revealed that eleven Class II Peroxidases were secreted by the fungus during fermentation and eight of them where tightly co-regulated with redox cycling enzymatic partners. CONCLUSION: As a peculiar feature of P. brumalis, we observed gene family extension, up-regulation and secretion of an abundant set of versatile peroxidases and manganese peroxidases, compared with other Polyporales species. The orchestrated secretion of an abundant set of these delignifying enzymes and redox cycling enzymatic partners could contribute to the delignification capabilities of the fungus. Our findings highlight the diversity of wood decay mechanisms present in Polyporales and the potentiality of further exploring this taxonomic order for enzymatic functions of biotechnological interest.

12.
Sci Rep ; 8(1): 6321, 2018 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-29679020

RESUMEN

Dark septate endophytes (DSE) are a form-group of root endophytic fungi with elusive functions. Here, the genomes of two common DSE of semiarid areas, Cadophora sp. and Periconia macrospinosa were sequenced and analyzed with another 32 ascomycetes of different lifestyles. Cadophora sp. (Helotiales) and P. macrospinosa (Pleosporales) have genomes of 70.46 Mb and 54.99 Mb with 22,766 and 18,750 gene models, respectively. The majority of DSE-specific protein clusters lack functional annotation with no similarity to characterized proteins, implying that they have evolved unique genetic innovations. Both DSE possess an expanded number of carbohydrate active enzymes (CAZymes), including plant cell wall degrading enzymes (PCWDEs). Those were similar in three other DSE, and contributed a signal for the separation of root endophytes in principal component analyses of CAZymes, indicating shared genomic traits of DSE fungi. Number of secreted proteases and lipases, aquaporins, and genes linked to melanin synthesis were also relatively high in our fungi. In spite of certain similarities between our two DSE, we observed low levels of convergence in their gene family evolution. This suggests that, despite originating from the same habitat, these two fungi evolved along different evolutionary trajectories and display considerable functional differences within the endophytic lifestyle.


Asunto(s)
Ascomicetos/genética , Endófitos/metabolismo , Hongos/genética , Hongos/metabolismo , Genómica/métodos , Micorrizas/genética , Raíces de Plantas/microbiología , Poaceae/microbiología
13.
Nat Genet ; 50(12): 1688-1695, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30349117

RESUMEN

Aspergillus section Nigri comprises filamentous fungi relevant to biomedicine, bioenergy, health, and biotechnology. To learn more about what genetically sets these species apart, as well as about potential applications in biotechnology and biomedicine, we sequenced 23 genomes de novo, forming a full genome compendium for the section (26 species), as well as 6 Aspergillus niger isolates. This allowed us to quantify both inter- and intraspecies genomic variation. We further predicted 17,903 carbohydrate-active enzymes and 2,717 secondary metabolite gene clusters, which we condensed into 455 distinct families corresponding to compound classes, 49% of which are only found in single species. We performed metabolomics and genetic engineering to correlate genotypes to phenotypes, as demonstrated for the metabolite aurasperone, and by heterologous transfer of citrate production to Aspergillus nidulans. Experimental and computational analyses showed that both secondary metabolism and regulation are key factors that are significant in the delineation of Aspergillus species.


Asunto(s)
Aspergillus/genética , Especiación Genética , Variación Genética , Genoma Fúngico , Aspergillus/clasificación , Aspergillus/metabolismo , Secuencia de Bases , Metabolismo de los Hidratos de Carbono/genética , Genoma Fúngico/genética , Familia de Multigenes , Filogenia , Especificidad de la Especie , Secuenciación Completa del Genoma
14.
Carbohydr Res ; 448: 166-174, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28434716

RESUMEN

Lytic polysaccharide monooxygenases of family AA9 catalyze the oxidative cleavage of glycosidic bonds in cellulose and related polysaccharides. The N-terminal half of AA9 LPMOs displays a huge sequence variability that is in contradiction with the substrate simplicity so far observed for these enzymes. To understand the cause of the high multigenicity that prevails in the family, we have performed a clustering analysis of the N-terminal region of 3400 sequences of family AA9 LPMOs, and have evaluated the coincidence of the clusters with distal visible features that may accompany functional differences. A method based on local pairwise alignments was devised to avoid the pitfalls of a global multiple alignment. Our analysis allowed the definition of 64 clusters, which successfully segregated several visible features associated to LPMO family AA9, such as the presence of carbohydrate-binding modules, of modules of unknown function and of the conspicuous H → R substitution at the first residue of the histidine brace that holds the catalytic copper. Our analysis shows that the hypervariability of the N-terminal half of the AA9 sequences is not driven by random evolution as sequence similarity does not follow solely taxonomy. The results suggest that some clusters are perhaps able to target chitin instead of cellulose, and that preference for C1 or C4 oxidation (or lack thereof), does not appear to constitute a strong evolutionary constraint. On an evolutionary standpoint, there seems to be little constraints that apply to the N-terminal half of the sequences other than the conservation of the histidine brace. The weak evolutionary constraints that apply to the N-terminal half of AA9 LPMOs explain both their hypervariability and multigenicity.


Asunto(s)
Biología Computacional , Oxidorreductasas/metabolismo , Polisacáridos/metabolismo , Secuencia de Aminoácidos , Análisis por Conglomerados , Evolución Molecular , Hongos/enzimología , Glucólisis , Oxidorreductasas/química
15.
J Biotechnol ; 246: 1-3, 2017 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-28216099

RESUMEN

Here we report the genome sequence of the ascomycete saprobic fungus Penicillium subrubescens FBCC1632/CBS132785 isolated from a Jerusalem artichoke field in Finland. The 39.75Mb genome containing 14,188 gene models is highly similar for that reported for other Penicillium species, but contains a significantly higher number of putative carbohydrate active enzyme (CAZyme) encoding genes.


Asunto(s)
Genoma Fúngico , Helianthus/microbiología , Penicillium/genética , Análisis de Secuencia de ADN/métodos , Secuencia de Bases , Biomasa , Metabolismo de los Hidratos de Carbono , Mapeo Cromosómico , Proteínas Fúngicas/genética , Penicillium/enzimología , Penicillium/aislamiento & purificación
16.
Nat Microbiol ; 2: 17087, 2017 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-28555641

RESUMEN

Cellulosomes are large, multiprotein complexes that tether plant biomass-degrading enzymes together for improved hydrolysis1. These complexes were first described in anaerobic bacteria, where species-specific dockerin domains mediate the assembly of enzymes onto cohesin motifs interspersed within protein scaffolds1. The versatile protein assembly mechanism conferred by the bacterial cohesin-dockerin interaction is now a standard design principle for synthetic biology2,3. For decades, analogous structures have been reported in anaerobic fungi, which are known to assemble by sequence-divergent non-catalytic dockerin domains (NCDDs)4. However, the components, modular assembly mechanism and functional role of fungal cellulosomes remain unknown5,6. Here, we describe a comprehensive set of proteins critical to fungal cellulosome assembly, including conserved scaffolding proteins unique to the Neocallimastigomycota. High-quality genomes of the anaerobic fungi Anaeromyces robustus, Neocallimastix californiae and Piromyces finnis were assembled with long-read, single-molecule technology. Genomic analysis coupled with proteomic validation revealed an average of 312 NCDD-containing proteins per fungal strain, which were overwhelmingly carbohydrate active enzymes (CAZymes), with 95 large fungal scaffoldins identified across four genera that bind to NCDDs. Fungal dockerin and scaffoldin domains have no similarity to their bacterial counterparts, yet several catalytic domains originated via horizontal gene transfer with gut bacteria. However, the biocatalytic activity of anaerobic fungal cellulosomes is expanded by the inclusion of GH3, GH6 and GH45 enzymes. These findings suggest that the fungal cellulosome is an evolutionarily chimaeric structure-an independently evolved fungal complex that co-opted useful activities from bacterial neighbours within the gut microbiome.


Asunto(s)
Celulosomas/genética , Proteínas Fúngicas/genética , Genómica , Neocallimastigales/enzimología , Neocallimastigales/genética , Unión Proteica , Multimerización de Proteína , Proteómica
17.
Genome Biol ; 18(1): 28, 2017 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-28196534

RESUMEN

BACKGROUND: The fungal genus Aspergillus is of critical importance to humankind. Species include those with industrial applications, important pathogens of humans, animals and crops, a source of potent carcinogenic contaminants of food, and an important genetic model. The genome sequences of eight aspergilli have already been explored to investigate aspects of fungal biology, raising questions about evolution and specialization within this genus. RESULTS: We have generated genome sequences for ten novel, highly diverse Aspergillus species and compared these in detail to sister and more distant genera. Comparative studies of key aspects of fungal biology, including primary and secondary metabolism, stress response, biomass degradation, and signal transduction, revealed both conservation and diversity among the species. Observed genomic differences were validated with experimental studies. This revealed several highlights, such as the potential for sex in asexual species, organic acid production genes being a key feature of black aspergilli, alternative approaches for degrading plant biomass, and indications for the genetic basis of stress response. A genome-wide phylogenetic analysis demonstrated in detail the relationship of the newly genome sequenced species with other aspergilli. CONCLUSIONS: Many aspects of biological differences between fungal species cannot be explained by current knowledge obtained from genome sequences. The comparative genomics and experimental study, presented here, allows for the first time a genus-wide view of the biological diversity of the aspergilli and in many, but not all, cases linked genome differences to phenotype. Insights gained could be exploited for biotechnological and medical applications of fungi.


Asunto(s)
Adaptación Biológica , Aspergillus/clasificación , Aspergillus/genética , Biodiversidad , Genoma Fúngico , Genómica , Aspergillus/metabolismo , Biomasa , Carbono/metabolismo , Biología Computacional/métodos , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Metilación de ADN , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Redes Reguladoras de Genes , Genómica/métodos , Humanos , Redes y Vías Metabólicas , Anotación de Secuencia Molecular , Familia de Multigenes , Oxidorreductasas/metabolismo , Filogenia , Plantas/metabolismo , Plantas/microbiología , Metabolismo Secundario/genética , Transducción de Señal , Estrés Fisiológico/genética
18.
Genome Announc ; 4(4)2016 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-27389259

RESUMEN

Cryptococcus sp. strain Mo29 was isolated from the Rainbow hydrothermal site on the Mid-Atlantic Ridge. Here, we present the draft genome sequence of this basidiomycetous yeast strain, which has highlighted its biotechnological potential as revealed by the presence of genes involved in the synthesis of secondary metabolites and biotechnologically important enzymes.

19.
Genome Announc ; 4(4)2016 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-27389260

RESUMEN

Cadophora malorum Mo12 was isolated from the Rainbow hydrothermal site on the Mid-Atlantic Ridge. We present the draft genome sequence of this filamentous fungal strain, which has high biotechnological potentials as revealed by the presence of genes encoding biotechnologically important enzymes and genes involved in the synthesis of secondary metabolites.

20.
PLoS One ; 11(6): e0154122, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27253872

RESUMEN

The fungus Cochliobolus miyabeanus causes severe leaf spot disease on rice (Oryza sativa) and two North American specialty crops, American wildrice (Zizania palustris) and switchgrass (Panicum virgatum). Despite the importance of C. miyabeanus as a disease-causing agent in wildrice, little is known about either the mechanisms of pathogenicity or host defense responses. To start bridging these gaps, the genome of C. miyabeanus strain TG12bL2 was shotgun sequenced using Illumina technology. The genome assembly consists of 31.79 Mbp in 2,378 scaffolds with an N50 = 74,921. It contains 11,000 predicted genes of which 94.5% were annotated. Approximately 10% of total gene number is expected to be secreted. The C. miyabeanus genome is rich in carbohydrate active enzymes, and harbors 187 small secreted peptides (SSPs) and some fungal effector homologs. Detoxification systems were represented by a variety of enzymes that could offer protection against plant defense compounds. The non-ribosomal peptide synthetases and polyketide synthases (PKS) present were common to other Cochliobolus species. Additionally, the fungal transcriptome was analyzed at 48 hours after inoculation in planta. A total of 10,674 genes were found to be expressed, some of which are known to be involved in pathogenicity or response to host defenses including hydrophobins, cutinase, cell wall degrading enzymes, enzymes related to reactive oxygen species scavenging, PKS, detoxification systems, SSPs, and a known fungal effector. This work will facilitate future research on C. miyabeanus pathogen-associated molecular patterns and effectors, and in the identification of their corresponding wildrice defense mechanisms.


Asunto(s)
Ascomicetos/genética , Genoma Fúngico/genética , Enfermedades de las Plantas/genética , Transcriptoma/genética , Ascomicetos/patogenicidad , Perfilación de la Expresión Génica , Oryza/microbiología , Panicum/microbiología , Moléculas de Patrón Molecular Asociado a Patógenos , Péptido Sintasas/genética , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Sintasas Poliquetidas/genética , Estados Unidos
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