RESUMEN
The anaerobic gut fungi (AGF) represent a coherent phylogenetic clade within the Mycota. Twenty genera have been described so far. Currently, the phylogenetic and evolutionary relationships between AGF genera remain poorly understood. Here, we utilized 52 transcriptomic datasets from 14 genera to resolve AGF inter-genus relationships using phylogenomics, and to provide a quantitative estimate (amino acid identity, AAI) for intermediate rank assignments. We identify four distinct supra-genus clades, encompassing all genera producing polyflagellated zoospores, bulbous rhizoids, the broadly circumscribed genus Piromyces, and the Anaeromyces and affiliated genera. We also identify the genus Khoyollomyces as the earliest evolving AGF genus. Concordance between phylogenomic outputs and RPB1 and D1/D2 LSU, but not RPB2, MCM7, EF1α or ITS1, phylogenies was observed. We combine phylogenomic analysis and AAI outputs with informative phenotypic traits to propose accommodating 14/20 AGF genera into four families: Caecomycetaceae fam. nov. (encompassing the genera Caecomyces and Cyllamyces), Piromycetaceae fam. nov. (encompassing the genus Piromyces), emend the description of the family Neocallimastigaceae to encompass the genera Neocallimastix, Orpinomyces, Pecoramyces, Feramyces, Ghazallomyces, Aestipascuomyces and Paucimyces, as well as the family Anaeromycetaceae to include the genera Oontomyces, Liebetanzomyces and Capellomyces in addition to Anaeromyces. We refrain from proposing families for the deeply branching genus Khoyollomyces and for genera with uncertain position (Buwchfawromyces, Joblinomyces, Tahromyces, Agriosomyces and Aklioshbomyces) pending availability of additional isolates and sequence data; and these genera are designated as 'genera incertae sedis' in the order Neocallimastigales. Our results establish an evolutionary-grounded Linnaean taxonomic framework for the AGF, provide quantitative estimates for rank assignments, and demonstrate the utility of RPB1 as an additional informative marker in Neocallimastigomycota taxonomy.
Asunto(s)
Neocallimastigales , Neocallimastigomycota , Humanos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Ácidos Grasos/químicaRESUMEN
Members of the anaerobic gut fungi (Neocallimastigomycota) reside in the rumen and alimentary tract of larger mammalian and some reptilian, marsupial and avian herbivores. The recent decade has witnessed a significant expansion in the number of described Neocallimastigomycota genera and species. However, the difficulties associated with the isolation and maintenance of Neocallimastigomycota strains has greatly complicated comparative studies to resolve inter- and intra-genus relationships. Here, we provide an updated outline of Neocallimastigomycota taxonomy. We critically evaluate various morphological, microscopic and phylogenetic traits previously and currently utilized in Neocallimastigomycota taxonomy, and provide an updated key for quick characterization of all genera. We then synthesize data from taxa description manuscripts, prior comparative efforts and molecular sequence data to present an updated list of Neocallimastigomycota genera and species, with an emphasis on resolving relationships and identifying synonymy between recent and historic strains. We supplement data from published manuscripts with information and illustrations from strains in the authors' collections. Twenty genera and 36 species are recognized, but the status of 10 species in the genera Caecomyces, Piromyces, Anaeromyces and Cyllamyces remains uncertain due to the unavailability of culture and conferre (cf.) strains, lack of sequence data, and/or inadequacy of available microscopic and phenotypic data. Six cases of synonymy are identified in the genera Neocallimastix and Caecomyces, and two names in the genus Piromyces are rejected based on apparent misclassification.
Asunto(s)
Neocallimastigomycota , Anaerobiosis , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hongos/genética , Mamíferos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Establishing a solid taxonomic framework is crucial for enabling discovery and documentation efforts. This ensures effective communication between scientists as well as reproducibility of results between laboratories, and facilitates the exchange and preservation of biological material. Such framework can only be achieved by establishing clear criteria for taxa characterization and rank assignment. Within the anaerobic fungi (phylum Neocallimastigomycota), the need for such criteria is especially vital. Difficulties associated with their isolation, maintenance and long-term storage often result in limited availability and loss of previously described taxa. To this end, we provide here a list of morphological, microscopic, phylogenetic and phenotypic criteria for assessment and documentation when characterizing newly obtained Neocallimastigomycota isolates. We also recommend a polyphasic rank-assignment scheme for novel genus-, species- and strain-level designations for newly obtained Neocallimastigomycota isolates.
Asunto(s)
Neocallimastigomycota , Anaerobiosis , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hongos/genética , Filogenia , ARN Ribosómico 16S/genética , Reproducibilidad de los Resultados , Análisis de Secuencia de ADNRESUMEN
The anaerobic gut fungi (AGF; phylum Neocallimastigomycota) reside in the alimentary tracts of herbivores. Multiple novel, yet-uncultured AGF taxa have recently been identified in culture-independent diversity surveys. Here, we report on the isolation and characterization of the first representative of the RH5 lineage from faecal samples of a wild blackbuck (Indian Antelope, Antilope cervicapra) from Sutton County, Texas, USA. The isolates displayed medium sized (2-4 mm) compact circular colonies on agar roll tubes and thin loose biofilm-like growth in liquid medium. Microscopic examination revealed monoflagellated zoospores and polycentric thalli with highly branched nucleated filamentous rhizomycelium, a growth pattern encountered in a minority of described AGF genera so far. The obtained isolates are characterized by formation of spherical vesicles at the hyphal tips from which multiple sporangia formed either directly on the spherical vesicles or at the end of sporangiophores. Phylogenetic analysis using the D1/D2 regions of the large ribosomal subunit (D1/D2 LSU) and the ribosomal internal transcribed spacer 1 (ITS1) revealed sequence similarities of 93.5 and 81.3%, respectively, to the closest cultured relatives (Orpinomyces joyonii strain D3A (D1/D2 LSU) and Joblinomyces apicalis strain GFH681 (ITS1). Substrate utilization experiments using the type strain (BB-3T) demonstrated growth capabilities on a wide range of mono-, oligo- and polysaccharides, including glucose, xylose, mannose, fructose, cellobiose, sucrose, maltose, trehalose, lactose, cellulose, xylan, starch and raffinose. We propose accommodating these novel isolates in a new genus and species, for which the name Paucimyces polynucleatus gen. nov., sp. nov. is proposed.
Asunto(s)
Antílopes/microbiología , Heces/microbiología , Neocallimastigomycota/clasificación , Filogenia , Anaerobiosis , Animales , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Neocallimastigomycota/aislamiento & purificación , Subunidades Ribosómicas Grandes , Análisis de Secuencia de ADN , TexasRESUMEN
The anaerobic gut fungi (AGF, Neocallimastigomycota) reside in the alimentary tracts of herbivores where they play a central role in the breakdown of plant material. Here, we report on the development of the hypervariable domains D1/D2 of the large ribosomal subunit (D1/D2 LSU) as a barcoding marker for the AGF. We generated a reference D1/D2 LSU database for all cultured AGF genera, as well as the majority of candidate genera encountered in prior internal transcribed spacer 1 (ITS1)-based surveys. Subsequently, a D1/D2 LSU-based diversity survey using long read PacBio SMRT sequencing was conducted on faecal samples from 21 wild and domesticated herbivores. Twenty-eight genera and candidate genera were identified, including multiple novel lineages that were predominantly, but not exclusively, identified in wild herbivores. Association between certain AGF genera and animal lifestyles, or animal host family was observed. Finally, to address the current paucity of AGF isolates, concurrent isolation efforts utilizing multiple approaches to maximize recovery yielded 216 isolates belonging to 12 different genera, several of which have no prior cultured-representatives. Our results establish the utility of D1/D2 LSU and PacBio sequencing for AGF diversity surveys, the culturability of multiple AGF taxa, and demonstrate that wild herbivores represent a yet-untapped reservoir of AGF diversity.
Asunto(s)
Microbioma Gastrointestinal , Herbivoria , Neocallimastigomycota/aislamiento & purificación , Subunidades Ribosómicas Grandes/genética , Animales , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Heces/microbiología , Neocallimastigomycota/clasificación , Neocallimastigomycota/genética , Filogenia , Análisis de Secuencia de ADNRESUMEN
Survival and growth of the anaerobic gut fungi (AGF; Neocallimastigomycota) in the herbivorous gut necessitate the possession of multiple abilities absent in other fungal lineages. We hypothesized that horizontal gene transfer (HGT) was instrumental in forging the evolution of AGF into a phylogenetically distinct gut-dwelling fungal lineage. The patterns of HGT were evaluated in the transcriptomes of 27 AGF strains, 22 of which were isolated and sequenced in this study, and 4 AGF genomes broadly covering the breadth of AGF diversity. We identified 277 distinct incidents of HGT in AGF transcriptomes, with subsequent gene duplication resulting in an HGT frequency of 2 to 3.5% in AGF genomes. The majority of HGT events were AGF specific (91.7%) and wide (70.8%), indicating their occurrence at early stages of AGF evolution. The acquired genes allowed AGF to expand their substrate utilization range, provided new venues for electron disposal, augmented their biosynthetic capabilities, and facilitated their adaptation to anaerobiosis. The majority of donors were anaerobic fermentative bacteria prevalent in the herbivorous gut. This study strongly indicates that HGT indispensably forged the evolution of AGF as a distinct fungal phylum and provides a unique example of the role of HGT in shaping the evolution of a high-rank taxonomic eukaryotic lineage.IMPORTANCE The anaerobic gut fungi (AGF) represent a distinct basal phylum lineage (Neocallimastigomycota) commonly encountered in the rumen and alimentary tracts of herbivores. Survival and growth of anaerobic gut fungi in these anaerobic, eutrophic, and prokaryote-dominated habitats necessitates the acquisition of several traits absent in other fungal lineages. We assess here the role of horizontal gene transfer as a relatively fast mechanism for trait acquisition by the Neocallimastigomycota postsequestration in the herbivorous gut. Analysis of 27 transcriptomes that represent the broad diversity of Neocallimastigomycota identified 277 distinct HGT events, with subsequent gene duplication resulting in an HGT frequency of 2 to 3.5% in AGF genomes. These HGT events have allowed AGF to survive in the herbivorous gut by expanding their substrate utilization range, augmenting their biosynthetic pathway, providing new routes for electron disposal by expanding fermentative capacities, and facilitating their adaptation to anaerobiosis. HGT in the AGF is also shown to be mainly a cross-kingdom affair, with the majority of donors belonging to the bacteria. This study represents a unique example of the role of HGT in shaping the evolution of a high-rank taxonomic eukaryotic lineage.
Asunto(s)
Evolución Molecular , Microbioma Gastrointestinal , Transferencia de Gen Horizontal , Neocallimastigomycota/genética , Animales , Evolución Biológica , Bovinos/microbiología , Tracto Gastrointestinal/microbiología , Genoma Fúngico , Cabras/microbiología , Neocallimastigomycota/fisiología , Ovinos/microbiologíaRESUMEN
The anaerobic gut fungi (AGF) inhabit the rumen and alimentary tracts of multiple ruminant and nonruminant herbivores, belong to a distinct phylum-level lineage (Neocallimastigomycota), and play an important role in plant biomass degradation in many herbivores. As part of a wider effort to obtain AGF with high lignocellulolytic capacities, we isolated and characterized four different AGF strains from the feces of cattle and sheep. Microscopically, isolates produced monocentric thalli and monoflagellated zoospores. Phylogenetic analysis revealed that all isolates formed a monophyletic cluster with strong bootstrap support as a sister clade to the genus Orpinomyces and close to Neocallimastix, an unexpected result because these two genera of AGF form polyflagellated zoospores. Isolates displayed a smooth biofilm-like growth in liquid medium and formed small (0.5-1 mm) pinpoint circular colonies on agar roll tubes. Both endogenous and exogenous sporangia were observed with variable shapes and sizes. Zoospores were mainly spherical, with diameters ranging between 3.8 and 12.5 µm, and mostly a single flagellum. All strains exhibited similar substrate utilization patterns and comparable cellulolytic and xylanolytic activities. Similar ITS1 sequences falling within the same distinctive clade were found on GenBank, with all environmental samples obtained from diverse ruminant and pseudoruminant hosts from three continents, but not from any hindgut-fermenting hosts. Given the high level of sequence divergence between our strains and closest cultured representatives and their distinct microscopic/macroscopic features, we propose a new genus, Pecoramyces, from the name of the taxonomic infraorder Pecora ("horned ruminants" or "higher ruminants"; derived from the Latin word for horned livestock), and a new species, P. ruminantium (since occurrence seems to be specific to ruminant/pseudoruminant foregut, but not hindgut-fermenting mammals).
Asunto(s)
Heces/microbiología , Tracto Gastrointestinal/microbiología , Neocallimastigomycota/clasificación , Animales , Bovinos , ADN de Hongos/genética , ADN Ribosómico/genética , ADN Espaciador Ribosómico/genética , Técnicas de Tipificación Micológica , Neocallimastigomycota/citología , Neocallimastigomycota/genética , Neocallimastigomycota/ultraestructura , Filogenia , Rumen/microbiología , Análisis de Secuencia de ADN , Ovinos , Esporangios/ultraestructura , Esporas Fúngicas/ultraestructuraRESUMEN
Despite their role in host nutrition, the anaerobic gut fungal (AGF) component of the herbivorous gut microbiome remains poorly characterized. Here, to examine global patterns and determinants of AGF diversity, we generate and analyze an amplicon dataset from 661 fecal samples from 34 mammalian species, 9 families, and 6 continents. We identify 56 novel genera, greatly expanding AGF diversity beyond current estimates (31 genera and candidate genera). Community structure analysis indicates that host phylogenetic affiliation, not domestication status and biogeography, shapes the community rather than. Fungal-host associations are stronger and more specific in hindgut fermenters than in foregut fermenters. Transcriptomics-enabled phylogenomic and molecular clock analyses of 52 strains from 14 genera indicate that most genera with preferences for hindgut hosts evolved earlier (44-58 Mya) than those with preferences for foregut hosts (22-32 Mya). Our results greatly expand the documented scope of AGF diversity and provide an ecologically and evolutionary-grounded model to explain the observed patterns of AGF diversity in extant animal hosts.
Asunto(s)
Micobioma , Animales , Micobioma/genética , Filogenia , Heces/microbiología , Sistema Digestivo , Evolución Biológica , MamíferosRESUMEN
We report on the isolation of the previously-uncultured Neocallimastigomycota SK4 lineage, by two independent research groups, from a wild aoudad sheep rumen sample (Texas, USA) and an alpaca fecal sample (Baden-Württemberg, Germany). Isolates from both locations showed near-identical morphological and microscopic features, forming medium-sized (2-5 mm) white filamentous colonies with a white center of sporangia, on agar roll tubes and a heavy biofilm in liquid media. Microscopic analysis revealed monocentric thalli, and spherical polyflagellated zoospores with 7-20 flagella. Zoospore release occurred through an apical pore as well as by sporangial wall rupturing, a duality that is unique amongst described anaerobic gut fungal strains. Isolates were capable of growing on a wide range of mono-, oligo-, and polysaccharide substrates as the sole carbon source. Phylogenetic assessment based on the D1-D2 28S large rRNA gene subunit (D1-D2 LSU) and internal transcribed spacer-1 (ITS-1) regions demonstrated high sequence identity (minimum identity of 99.07% and 96.96%, respectively) between all isolates; but low sequence identity (92.4% and 86.7%, respectively) to their closest cultured relatives. D1-D2 LSU phylogenetic trees grouped the isolates as a new monophyletic clade within the Orpinomyces-Neocallimastix-Pecoramyces-Feramyces-Ghazallamyces supragenus group. D1-D2 LSU and ITS-1 sequences recovered from the obtained isolates were either identical or displayed extremely high sequence similarity to sequences recovered from the same aoudad sheep sample on which isolation was conducted, as well as several sequences recovered from domestic sheep and few other herbivores. Interestingly, members of the SK4 clade seem to be encountered preferably in animals grazing on summer pasture. We hence propose accommodating these novel isolates in a new genus, Aestipascuomyces (derived from the Latin word for "summer pasture"), and a new species, A. dupliciliberans. The type strain is Aestipascuomycesdupliciliberans strain R4.
RESUMEN
We isolated and characterized 65 anaerobic gut fungal (AGF; Neocallimastigomycota) strains from fecal samples of five wild (W, axis deer, white-tailed deer, Boer goat, mouflon, and Nilgiri tahr), one zoo-housed (Z, zebra), and three domesticated (D, horse, sheep, and goat) herbivores in the US states of Texas (TX) and Oklahoma (OK), Wales (WA), and the Indian states of Kerala (KE) and Haryana (HA). Phylogenetic assessment using the D1-D2 regions of the large subunit (28S) rDNA and internal transcribed spacer 1 (ITS1) identified seven monophyletic clades that are distinct from all currently recognized AGF genera. All strains displayed monocentric thalli and produced exclusively or predominantly monoflagellate zoospores, with the exception of axis deer strains, which produced polyflagellate zoospores. Analysis of amplicon-based AGF diversity surveys indicated that zebra and horse strains are representatives of uncultured AL1 group, whereas domesticated goat and sheep strains are representatives of uncultured AL5 group, previously encountered in fecal and rumen samples of multiple herbivores. The other five lineages, all of which were isolated from wild herbivores, have not been previously encountered in such surveys. Our results significantly expand the genus-level diversity within the Neocallimastigomycota and strongly suggest that wild herbivores represent a yet-untapped reservoir of AGF diversity. We propose seven novel genera and eight novel Neocallimastigomycota species to comprise these strains, for which we propose the names Agriosomyces longus (mouflon and wild Boer goat), Aklioshbomyces papillarum (white-tailed deer), Capellomyces foraminis (wild Boar goat), and C. elongatus (domesticated goat), Ghazallomyces constrictus (axis deer), Joblinomyces apicalis (domesticated goat and sheep), Khoyollomyces ramosus (zebra-horse), and Tahromyces munnarensis (Nilgiri tahr).
Asunto(s)
Animales Domésticos/microbiología , Animales Salvajes/microbiología , Animales de Zoológico/microbiología , Herbivoria , Neocallimastigomycota/clasificación , Neocallimastigomycota/genética , Filogenia , Anaerobiosis , Animales , ADN de Hongos/genética , ADN Ribosómico/genética , Ciervos/microbiología , Heces/microbiología , Femenino , Cabras/microbiología , Herbivoria/clasificación , Caballos/microbiología , Masculino , Neocallimastigomycota/aislamiento & purificación , Ovinos/microbiología , Porcinos/microbiologíaRESUMEN
The anaerobic gut fungi (AGF), or Neocallimastigomycota, inhabit the rumen and alimentary tract of herbivorous mammals, where they play important roles in the degradation of plant fiber. Comparative genomic and phylogenomic analyses of the AGF have long been hampered by their fastidious growth condition, as well as their large (up to 200 Mb) and AT-biased (78 to 84%) genomes. We sequenced 21 AGF transcriptomes and combined them with 5 available AGF genome sequences to explore their evolutionary relationships, time their divergence, and characterize gene gain/loss patterns associated with their evolution. We estimate that the most recent common ancestor of the AGF diverged 66 (±10) million years ago, a time frame that coincides with the evolution of grasses (Poaceae), as well as the mammalian transition from insectivory to herbivory. The concordance of independent estimations suggests that AGF have been important in shaping the success of mammalian herbivory transition by improving the efficiency of energy acquisition from recalcitrant plant materials. Comparative genomics identified multiple lineage-specific genes in the AGF, two of which were acquired from rumen gut bacteria and animal hosts via horizontal gene transfer (HGT). A third AGF domain, plant-like polysaccharide lyase, represents a novel gene in fungi that potentially aids AGF to degrade pectin. Analysis of genomic and transcriptomic sequences confirmed both the presence and expression of these lineage-specific genes in nearly all AGF clades. These genetic elements may contribute to the exceptional abilities of AGF to degrade plant biomass and enable metabolism of the rumen microbes and animal hosts.IMPORTANCE Anaerobic fungi living in the rumen of herbivorous mammals possess an extraordinary ability to degrade plant biomass. We examined the origin and genomic composition of these poorly characterized anaerobic gut fungi using both transcriptome and genomic data. Phylogenomics and molecular dating analyses found remarkable concurrence of the divergence times of the rumen fungi, the forage grasses, and the dietary shift of ancestral mammals from primarily insectivory to herbivory. Comparative genomics identified unique machinery in these fungi to utilize plant polysaccharides. The rumen fungi were also identified with the ability to code for three protein domains with putative functions in plant pectin degradation and microbial defense, which were absent from all other fungal organisms (examined over 1,000 fungal genomes). Two of these domains were likely acquired from rumen gut bacteria and animal hosts separately via horizontal gene transfer. The third one is a plant-like polysaccharide lyase, representing a unique fungal enzyme with potential pectin breakdown abilities.
RESUMEN
Anaerobic gut fungi are common inhabitants of the alimentary tracts of herbivorous animals. Nine different Neocallimastigomycota genera have been described so far. However, culture-independent diversity surveys suggest the presence of numerous, yet-uncultured Neocallimastigomycota genera. Here, we report on the isolation and characterization of the first cultured representatives of Neocallimastigomycota clade AL6, originally identified in culture-independent surveys of fecal samples from captive wild animals. Six strains were isolated from rumen and fecal samples of a wild Barbary sheep (Ammotragus lervia) and a wild fallow deer (Dama dama) in Texas, USA. The isolates displayed medium-sized (3-7 mm), circular, beige colonies with filamentous edges and a dark center on agar roll tubes. Microscopic analysis revealed monocentric thalli with both endogenous and exogenous sporangial development patterns. Zoospores were spherical, with a diameter of 9.6 ± 1.9 µm, and polyflagellated, with 7-16 flagella. Phylogenetic analysis based on nuc rDNA ITS1 region and D1-D2 domains of nuc 28S rDNA revealed that the isolated strains formed a single monophyletic and bootstrap-supported clade distinct from all currently described Neocallimastigomycota genera. Substrate utilization experiments using the type strain (F3a) demonstrated robust and fast growth on sugars and plant biomass, as well as the capability to metabolize a wide range of mono-, oligo-, and polysaccharides, including galactose, arabinose, alginate, and pectin. On the basis of the morphological, physiological, and phylogenetic analyses, we propose to accommodate these isolates in a new genus, Feramyces (derived from the Latin word for "wild" to reflect their isolation and apparent distribution in undomesticated herbivores), and a new species, F. austinii. The type strain is Feramyces austinii F3a.
Asunto(s)
Animales Salvajes/microbiología , Antílopes , Quitridiomicetos/clasificación , Ciervos/microbiología , Heces/microbiología , Rumen/microbiología , Ovinos/microbiología , Anaerobiosis , Animales , Quitridiomicetos/citología , Quitridiomicetos/genética , Quitridiomicetos/fisiología , ADN de Hongos/genética , ADN Ribosómico/genética , Filogenia , Análisis de Secuencia de ADN , TexasRESUMEN
Ten different anaerobic gut fungal strains were isolated from fecal samples of cow and goat in Oklahoma, USA. The isolates displayed polycentric thalli, uniflagellated zoospores, and sausage-shaped hyphal constrictions, all characteristic of the genus Anaeromyces, and lobed or appressorium-like structures on the hyphae, previously reported in Anaeromyces elegans but not in A. mucronatus or A. robustus. Further, the strains exhibited highly coiled and entangled hyphae previously unreported in the Neocallimastigomycota, but resembling fungal traps previously observed in multiple nematophagous fungi. Scanning electron micrographs of isolates grown on switchgrass showed entrapment of plant material by the hyphal coils and the penetration of plant fibers at various sites by the appressorium-like structures. Molecular analysis based on sequences of both partial nuc rDNA ITS1 spacer region and the D1-D2 domains of the nuc28S rDNA confirmed the classification of all isolates in Anaeromyces and confirmed their phylogenetic distance from the available A. mucronatus and A. robustus sequences. On the basis of morphological and phylogenetic distinctions, we conclude that these strains represent a new Anaeromyces species, for which A. contortus is proposed.
Asunto(s)
Bovinos/microbiología , Heces/microbiología , Cabras/microbiología , Neocallimastigales/clasificación , Neocallimastigales/citología , Filogenia , Anaerobiosis , Animales , ADN de Hongos/genética , ADN Ribosómico/genética , Hifa/citología , Neocallimastigales/genética , Oklahoma , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
Anaerobic gut fungi (AGF) represent a basal fungal lineage (phylum Neocallimastigomycota) that resides in the rumen and alimentary tracts of herbivores. The AGF reproduce asexually, with a life cycle that involves flagellated zoospores released from zoosporangia followed by encystment, germination and the subsequent development of rhizomycelia. A fast and reliable approach for AGF spore collection is critical not only for developmental biology studies, but also for molecular biological (e.g. AMT-transformation and RNAi) approaches. Here, we developed and optimized a simple and reliable procedure for the collection of viable, competent, and developmentally synchronized AGF spores under strict anaerobic conditions. The approach involves growing AGF on agar medium in serum bottles under anaerobic conditions, and flooding the observed aerial growth to promote spore release from sporangia into the flooding suspension. The released spores are gently collected using a wide bore sterile needle. Process optimization resulted in the recovery of up to 7×10(9) spores per serum bottle. Further, the released spores exhibited synchronized development from flagellated spores to encysted spores and finally to germinating spores within 90min from the onset of flooding. At the germinating spore stage, the obtained spores were competent, and readily uptook small interfering RNA (siRNA) oligonucleotides. Finally, using multiple monocentric and polycentric AGF isolates, we demonstrate that AGF grown on agar surface could retain viability for up to 16weeks at 39°C, and hence this solid surface growth procedure represents a simple, cryopreservative- and freezing temperature-free approach for AGF storage.
Asunto(s)
Neocallimastigomycota/aislamiento & purificación , Neocallimastigomycota/fisiología , Esporas Fúngicas/genética , Esporas Fúngicas/aislamiento & purificación , Anaerobiosis , Medios de Cultivo , Viabilidad Microbiana , Neocallimastigomycota/genética , Preservación Biológica , ARN Interferente Pequeño , Esporas Fúngicas/crecimiento & desarrolloRESUMEN
Staphylococcus hominis is a predominant member of the human skin microbiome. We here report on the genomic analysis of Staphylococcus hominis strain Hudgins that was isolated from the wrist area of human skin. The partial genome assembly of S. hominis Hudgins consists of 2,211,863 bp of DNA with 2174 protein-coding genes and 90 RNA genes. Based on the genomic analysis of KEGG pathways, the organism is expected to be a versatile heterotroph potentially capable of hydrolyzing the sugars glucose, fructose, mannose, and the amino acids alanine, aspartate, glutamate, glycine, threonine, cysteine, methionine, valine, isoleucine, leucine, lysine, arginine, phenylalanine, tyrosine, and tryptophan for energy production through aerobic respiration, with occasional lactate and acetate fermentation. Evidence for poly-gamma glutamate capsule and type IV Com system pili were identified in the genome. Based on COG analysis, the genome of S. hominis Hudgins clusters away from the previously published S. hominis genome ZBW5.
RESUMEN
Microbacterium oleivorans is a predominant member of hydrocarbon-contaminated environments. We here report on the genomic analysis of M. oleivorans strain Wellendorf that was isolated from an indoor door handle. The partial genome of M. oleivorans strain Wellendorf consists of 2,916,870 bp of DNA with 2831 protein-coding genes and 49 RNA genes. The organism appears to be a versatile mesophilic heterotroph potentially capable of hydrolysis a suite of carbohydrates and amino acids. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of glucose, fructose, rhamnose, galactose, xylose, arabinose, alanine, aspartate, asparagine, glutamate, serine, glycine, threonine and cysteine. This is the first detailed analysis of a Microbacterium oleivorans genome.
RESUMEN
The genus Pantoea is a predominant member of host-associated microbiome. We here report on the genomic analysis of Pantoea eucrina strain Russ that was isolated from a trashcan at Oklahoma State University, Stillwater, OK. The draft genome of Pantoea eucrina strain Russ consists of 3,939,877 bp of DNA with 3704 protein-coding genes and 134 RNA genes. This is the first report of a genome sequence of a member of Pantoea eucrina. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of all amino acids as well as glucose, fructose, mannose, xylose, arabinose and galactose, suggesting the organism is a versatile heterotroph. The genome also encodes an extensive secretory machinery including types I, II, III, IV, and Vb secretion systems, and several genes for pili production including the new usher/chaperone system (pfam 05,229). The implications of these systems for opportunistic pathogenesis are discussed.
RESUMEN
Micrococcus luteus is a predominant member of skin microbiome. We here report on the genomic analysis of Micrococcus luteus strain O'Kane that was isolated from an elevator. The partial genome assembly of Micrococcus luteus strain O'Kane is 2.5 Mb with 2256 protein-coding genes and 62 RNA genes. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of glucose, galactose, fructose, mannose, alanine, aspartate, asparagine, glutamate, glutamine, glycine, serine, cysteine, methionine, arginine, proline, histidine, phenylalanine, and fatty acids. Genomic comparison to other M. luteus representatives identified the potential to degrade polyhydroxybutyrates, as well as several antibiotic resistance genes absent from other genomes.
RESUMEN
Pseudomonas moraviensis is a predominant member of soil environments. We here report on the genomic analysis of Pseudomonas moraviensis strain Devor that was isolated from a gate at Oklahoma State University, Stillwater, OK, USA. The partial genome of Pseudomonas moraviensis strain Devor consists of 6016489 bp of DNA with 5290 protein-coding genes and 66 RNA genes. This is the first detailed analysis of a P. moraviensis genome. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of fructose, xylose, mannose and all amino acids with the exception of tryptophan and valine, implying that the organism is a versatile heterotroph. The genome of P. moraviensis strain Devor was rich in transporters and, based on COG analysis, did not cluster closely with P. moraviensis R28-S genome, the only previous report of a P. moraviensis genome with a native mercury resistance plasmid.
RESUMEN
We report the draft genome sequence of Arthrobacter sp. strain Edens01, isolated from a leaf surface of a Rosa hybrid plant as part of the Howard Hughes Medical Institute-funded Student Initiated Microbial Discovery (SIMD) project. The genome has a total size of 3,639,179 bp and contig N50 of 454,897 bp.