RESUMO
By investigating wet and dry age-related ripening of beef, Pseudomonas strains V3/3/4/13T and V3/K/3/5T were isolated. Strain V3/3/4/13T exhibited more than 99â% 16S rRNA gene-based similarity to Pseudomonas fragi and other members of this group, while isolate V3/K/3/5T was very close to Pseudomonas veronii and a number of relatives within the Pseudomonas fluorescens group. Additional comparisons of complete rpoB sequences and draft genomes allowed us to place isolate V3/3/4/13T close to Pseudomonas deceptionensis DSM 26521T. In the case of V3/K/3/5T the closest relative was P. veronii DSM 11331T. Average nucleotide identity (ANIb) and digital DNA-DNA hybridization (dDDH) values calculated from the draft genomes of V3/3/4/13T and P. deceptionensis DSM 26521T were 88.5 and 39.8â%, respectively. For V3/K/3/5T and its closest relative P. veronii DSM 11331T, the ANIb value was 95.1â% and the dDDH value was 60.7â%. The DNA G+C contents of V3/3/4/13T and V3/K/3/5T were 57.4 and 60.8 mol%, respectively. Predominant fatty acids were C16â:â0, C18â:â1 ω7c, C17â:â0 cyclo and summed feature C16â:â1 ω7ct/C15â:â0 iso 2OH. The main respiratory quinones were Q9, with minor proportions of Q8 and, in the case of V3/K/3/5T, additional Q10. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and, in the case of V3/K/3/5T, additional phosphatidylcholine. Based on the combined data, isolates V3/3/4/13T and V3/K/3/5T should be considered as representatives of two novel Pseudomonas species. The type strain of the newly proposed Pseudomonas kulmbachensis sp. nov. is V3/3/4/13T (=DSM 113654T=LMG 32520T), a second strain belonging to the same species is FLM 004-28 (=DSM 113604=LMG 32521); the type strain for the newly proposed Pseudomonas paraveronii sp. nov. is V3/K/3/5T (=DSM 113573T=LMG 32518T) with a second isolate FLM 11 (=DSM 113572=LMG 32519).
Assuntos
Galinhas , Ácidos Graxos , Animais , Bovinos , Composição de Bases , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Filogenia , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Pseudomonas/genética , NucleotídeosRESUMO
BACKGROUND: Industrial by-products accrue in most agricultural or food-related production processes, but additional value chains have already been established for many of them. Crude glycerol has a 60% lower market value than commercial glucose, as large quantities are produced in the biodiesel industry, but its valorisation is still underutilized. Due to its high carbon content and the natural ability of many microorganisms to metabolise it, microbial upcycling is a suitable option for this waste product. RESULTS: In this work, the use of crude glycerol for the production of the value-added compound itaconate is demonstrated using the smut fungus Ustilago maydis. Starting with a highly engineered strain, itaconate production from an industrial glycerol waste stream was quickly established on a small scale, and the resulting yields were already competitive with processes using commercial sugars. Adaptive laboratory evolution resulted in an evolved strain with a 72% increased growth rate on glycerol. In the subsequent development and optimisation of a fed-batch process on a 1.5-2 L scale, the use of molasses, a side stream of sugar beet processing, eliminated the need for other expensive media components such as nitrogen or vitamins for biomass growth. The optimised process was scaled up to 150 L, achieving an overall titre of 72 g L- 1, a yield of 0.34 g g- 1, and a productivity of 0.54 g L- 1 h- 1. CONCLUSIONS: Pilot-scale itaconate production from the complementary waste streams molasses and glycerol has been successfully established. In addition to achieving competitive performance indicators, the proposed dual feedstock strategy offers lower process costs and carbon footprint for the production of bio-based itaconate.
Assuntos
Glicerol , Succinatos , Glicerol/metabolismo , Succinatos/metabolismo , Glucose/metabolismoRESUMO
This article describes some use case studies and self-assessments of FAIR status of de.NBI services to illustrate the challenges and requirements for the definition of the needs of adhering to the FAIR (findable, accessible, interoperable and reusable) data principles in a large distributed bioinformatics infrastructure. We address the challenge of heterogeneity of wet lab technologies, data, metadata, software, computational workflows and the levels of implementation and monitoring of FAIR principles within the different bioinformatics sub-disciplines joint in de.NBI. On the one hand, this broad service landscape and the excellent network of experts are a strong basis for the development of useful research data management plans. On the other hand, the large number of tools and techniques maintained by distributed teams renders FAIR compliance challenging.
Assuntos
Gerenciamento de Dados/métodos , Metadados , Redes Neurais de Computação , Proteômica/métodos , Software , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cooperação Internacional , Fenótipo , Plantas/genética , Proteoma , Autoavaliação (Psicologia) , Fluxo de TrabalhoRESUMO
Strain TÜ4103T was originally sampled from Java, Indonesia and deposited in the Tübingen strain collection under the name 'Streptomyces sp.'. The strain was found to be an antibiotic producer as strain TÜ4103T showed bioactivity against Gram-positive bacteria, such as Bacillus subtilis and Kocuria rhizophila in bioassays. Strain TÜ4103T showed 16S rRNA gene sequence similarity of 99.65â% to Kitasatospora cheerisanensis DSM 101999T and 98.82â% to Kitasatospora niigatensis DSM 44781T and Kitasatospora cineracea DSM 44780T. Genome-based phylogenetic analysis revealed that strain TÜ4103T is closely related to K. cineracea DSM 44780T and K. niigatensis DSM 44781T. The digital DNA-DNA hybridization values between the genome sequences of strain TÜ4103T and its closest phylogenomic relatives, strains DSM 44780T and DSM 44781T, were 43.0 and 42.9â%, respectively. Average nucleotide identity (ANI) values support this claim, with the highest ANI score of 91.14â% between TÜ4103T and K. niigatensis being closely followed by an ANI value of 91.10â% between K. cineracea and TÜ4103T. The genome of TÜ4103T has a size of 7.91 Mb with a G+C content of 74.05 mol%. Whole-cell hydrolysates of strain TÜ4103T are rich in meso-diaminopimelic acid, and rhamnose, galactose and mannose are characteristic as whole-cell sugars. The phospholipid profile contains phosphatidylethanolamine, diphosphatidylglycerol and glycophospholipid. The predominant menaquinones (>93.5â%) are MK-9(H8) and MK-9(H6). Based on the phenotypic, genotypic and genomic characteristics, strain TÜ4103T (=DSM 114396T=CECT 30712T) merits recognition as the type strain of a novel species of the genus Kitasatospora, for which the name Kitasatospora fiedleri sp. nov. is proposed.
Assuntos
Antibacterianos , Ácidos Graxos , Composição de Bases , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Ácidos Graxos/química , NucleotídeosRESUMO
It is currently assumed that around 100 million years ago, the common ancestor to the Fabales, Fagales, Rosales and Cucurbitales in Gondwana, developed a root nodule symbiosis with a nitrogen-fixing bacterium. The symbiotic trait evolved first in Frankia cluster-2; thus, strains belonging to this cluster are the best extant representatives of this original symbiont. Most cluster-2 strains could not be cultured to date, except for Frankia coriariae, and therefore many aspects of the symbiosis are still elusive. Based on phylogenetics of cluster-2 metagenome-assembled genomes (MAGs), it has been shown that the genomes of strains originating in Eurasia are highly conserved. These MAGs are more closely related to Frankia cluster-2 in North America than to the single genome available thus far from the southern hemisphere, i.e., from Papua New Guinea.To unravel more biodiversity within Frankia cluster-2 and predict routes of dispersal from Gondwana, we sequenced and analysed the MAGs of Frankia cluster-2 from Coriaria japonica and Coriaria intermedia growing in Japan, Taiwan and the Philippines. Phylogenetic analyses indicate there is a clear split within Frankia cluster-2, separating a continental from an island lineage. Presumably, these lineages already diverged in Gondwana.Based on fossil data on the host plants, we propose that these two lineages dispersed via at least two routes. While the continental lineage reached Eurasia together with their host plants via the Indian subcontinent, the island lineage spread towards Japan with an unknown host plant.
Assuntos
Frankia , Magnoliopsida , Frankia/genética , Magnoliopsida/genética , Metagenoma , Fixação de Nitrogênio , Filogenia , Plantas/genética , Simbiose/genéticaRESUMO
Endophytic fungi have been recognized as prolific producers of chemically diverse secondary metabolites. In this work, we describe a new representative of the order Helotiales isolated from the medicinal plant Bergenia pacumbis. Several bioactive secondary metabolites were produced by this Helotiales sp. BL 73 isolate grown on rice medium, including cochlioquinones and isofusidienols. Sequencing and analysis of the approximately 59-Mb genome revealed at least 77 secondary metabolite biosynthesis gene clusters, of which several could be associated with detected compounds or linked to previously reported molecules. Four terpene synthase genes identified in the BL73 genome were codon optimized and expressed, together with farnesyl-, geranyl-, and geranylgeranyl-pyrophosphate synthases, in Streptomyces spp. An analysis of recombinant strains revealed the production of linalool and its oxidized form, terpenoids typically associated with plants, as well as a yet unidentified terpenoid. This study demonstrates the importance of a complex approach to the investigation of the biosynthetic potential of endophytic fungi using both conventional methods and genome mining. IMPORTANCE Endophytic fungi represent an as yet underexplored source of secondary metabolites, of which some may have industrial and medical applications. We isolated a slow-growing fungus belonging to the order Helotiales from the traditional medicinal plant Bergenia pacumbis and characterized its potential to biosynthesize secondary metabolites. We used cultivation of the isolate with a subsequent analysis of compounds produced, bioinformatics-based mining of the genome, and heterologous expression of several terpene synthase genes. Our study revealed that this Helotiales isolate has enormous potential to produce structurally diverse natural products, including polyketides, nonribosomally synthesized peptides, terpenoids, and ribosomally synthesized and posttranslationally modified peptides (RiPPs). Identification of meroterpenoids and xanthones, along with establishing a link between these molecules and their putative biosynthetic genes, sets the stage for investigation of the respective biosynthetic pathways. The heterologous production of terpenoids suggests that this approach can be used for the discovery of new compounds belonging to this chemical class using Streptomyces bacteria as hosts.
Assuntos
Ascomicetos , Streptomyces , Ascomicetos/genética , Vias Biossintéticas/genética , Família Multigênica , Metabolismo Secundário , Streptomyces/genéticaRESUMO
An actinobacterial strain, CMB-FB, was isolated from surface-sterilized root nodules of a Coriaria intermedia plant growing along Halsema Highway in the province of Benguet (Luzon, Philippines). The 16S rRNA gene sequence of CMB-FB showed high sequence similarity to those of the type strains of Streptomyces rishiriensis (99.4â%), Streptomyces humidus (99.1â%), Streptomyces cacaoi subsp. asoensis (99.0â%), and Streptomyces phaeofaciens (98.6â%). The major menaquinones of CMB-FB were composed of MK-9(H4), MK-9(H6) and MK-9(H8), and there was a minor contribution of MK-9(H10). The polar lipid profile consisted of phosphatidylethanolamine, unidentified aminolipids and phospholipids, a glycophospholipid and four unidentified lipids. The diagnostic diamino acid of the peptidoglycan was meso-diaminopimelic acid. The major fatty acids were iso-C16â:â0, anteiso-C15â:â0 and anteiso-C17â:â0. The results of physiological analysis indicated that CMB-FB was mesophilic. The results of phylogenetic, genome-genome distance calculation and average nucleotide identity analysis indicated that the isolated strain represents the type strain of a novel species. On the basis of these results, strain CMB-FB (=DSM 112754T=LMG 32457T) is proposed as the type strain of the novel species Streptomyces coriariae sp. nov.
Assuntos
Ácidos Graxos , Streptomyces , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Filipinas , Fosfolipídeos/química , Vitamina K 2/químicaRESUMO
An anaerobic bacterial strain, designated strain M3/9T, was isolated from a laboratory-scale biogas fermenter fed with maize silage supplemented with 5â% wheat straw. Cells were straight, non-motile rods, which stained Gram-negative. Optimal growth occurred between 30 and 40°C, at pH 7.5-8.5, and up to 3.9â% (w/v) NaCl was tolerated. When grown on peptone from casein and soymeal, strain M3/9T produced mainly acetic acid, ethanol, and isobutyric acid. The major cellular fatty acids of the novel strain were C16â:â0 and C16â:â0 DMA. The genome of strain M3/9T is 3757ââ330 bp in size with a G+C content of 38.45âmol%. Phylogenetic analysis allocated strain M3/9T within the family Lachnospiraceae with Clostridium colinum DSM 6011T and Anaerotignum lactatifermentans DSM 14214T being the most closely related species sharing 57.86 and 56.99% average amino acid identity and 16S rRNA gene sequence similarities of 91.58 and 91.26â%, respectively. Based on physiological, chemotaxonomic and genetic data, we propose the description of a novel species and genus Anaeropeptidivorans aminofermentans gen. nov., sp. nov., represented by the type strain M3/9T (=DSM 100058T=LMG 29527T). In addition, an emended description of Clostridium colinum is provided.
Assuntos
Biocombustíveis , Ácidos Graxos , Filogenia , RNA Ribossômico 16S/genética , Ácidos Graxos/química , Composição de Bases , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Análise de Sequência de DNA , Clostridium/genéticaRESUMO
Microplastics in marine ecosystems are colonized by diverse prokaryotic and eukaryotic communities. How these communities and their functional profiles are shaped by the artificial surfaces remains broadly unknown. In order to close this knowledge gap, we set up an in situ experiment with pellets of the polyolefin polymer polyethylene (PE), the aromatic hydrocarbon polymer polystyrene (PS), and wooden beads along a coastal to estuarine gradient in the Baltic Sea, Germany. We used an integrated metagenomics/metaproteomics approach to evaluate the genomic potential as well as protein expression levels of aquatic plastic biofilms. Our results suggest that material properties had a minor influence on the plastic-associated assemblages, as genomic and proteomic profiles of communities associated with the structurally different polymers PE and PS were highly similar, hence polymer-unspecific. Instead, it seemed that these communities were shaped by biogeographic factors. Wood, on the other hand, induced the formation of substrate-specific biofilms and served as nutrient source itself. Our study indicates that, while PE and PS microplastics may be relevant in the photic zone as opportunistic colonization grounds for phototrophic microorganisms, they appear not to be subject to biodegradation or serve as vectors for pathogenic microorganisms in marine habitats.
Assuntos
Microplásticos , Poluentes Químicos da Água , Biofilmes , Ecossistema , Plásticos , Proteômica , Propriedades de SuperfícieRESUMO
ELIXIR is a pan-European intergovernmental organisation for life science that aims to coordinate bioinformatics resources in a single infrastructure across Europe; bioinformatics training is central to its strategy, which aims to develop a training community that spans all ELIXIR member states. In an evidence-based approach for strengthening bioinformatics training programmes across Europe, the ELIXIR Training Platform, led by the ELIXIR EXCELERATE Quality and Impact Assessment Subtask in collaboration with the ELIXIR Training Coordinators Group, has implemented an assessment strategy to measure quality and impact of its entire training portfolio. Here, we present ELIXIR's framework for assessing training quality and impact, which includes the following: specifying assessment aims, determining what data to collect in order to address these aims, and our strategy for centralised data collection to allow for ELIXIR-wide analyses. In addition, we present an overview of the ELIXIR training data collected over the past 4 years. We highlight the importance of a coordinated and consistent data collection approach and the relevance of defining specific metrics and answer scales for consortium-wide analyses as well as for comparison of data across iterations of the same course.
Assuntos
Biologia Computacional/educação , Controle de Qualidade , Algoritmos , Pesquisa Biomédica , Biologia Computacional/normas , Currículo , Coleta de Dados , Bases de Dados Factuais , Educação Continuada , Europa (Continente) , Avaliação de Programas e Projetos de Saúde , Reprodutibilidade dos Testes , Pesquisadores , Software , Interface Usuário-ComputadorRESUMO
A polyphasic approach was applied to investigate the diversity of microbiota that evolved during cold storage beef ripening. Isolate V4/DAB/S4/2aT with a unique BOX-rep-PCR fingerprint profile revealed more than 99â% nucleotide identities upon pairwise comparisons of 16S rDNA sequences from the type strains Pseudomonas versuta DSM 101070T, Pseudomonas saxonica DSM 108989T, Pseudomonas deceptionensis DSM 26521T and Pseudomonas weihenstephanensis DSM 29166T, placing it within the Pseudomonas fragi / lundensis branch of the genus Pseudomonas. Additional rpoB based comparison revealed P. versuta DSM 101070T as the nearest relative, with 98.5â% nucleotide identity. Calculation of ANIb values of the V4/DAB/S4/2aT draft genome identified P. versuta DSM 101070T with 90.1â%, P. deceptionensis DSM 26521T with 85.1â%, P. fragi DSM 3456T with 84.4â%, Pseudomonas psychrophila DSM 17535T and Pseudomonas bubulae DSM 107389T with 84.2â% similarities each. Pairwise genome-to-genome distance calculations [digital DNA-DNA hybridization (dDDH)] resulted in values of 47.1, 35.1, 34.8, 34.2 and 34.1â%, respectively. A second isolate was detected years later in ground beef and showed ANIb values of 99.3â% and dDDH of 96.1â% relatedness to V4/DAB/S4/2aT. The DNA G+C content was 58.6 mol% for both isolates. The predominant cellular fatty acids of V4/DAB/S4/2aT were C16â:â0, C18â:â1ω7c, C17â:â0 cyclo and a summed feature containing C16â:â1ω7c and/or C15â:â0 iso 2-OH. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol, the major respiratory quinone was Q9, with a small portion of Q8. The combined data on genotypic and phenotypic features support the proposal of a novel species, for which the name Pseudomonas paraversuta sp. nov. is proposed. The type strain is V4/DAB/S4/2aT (=DSM 111361T=LMG 31844T) and a second isolate is UBT376 (=DSM 111360=LMG 31845).
Assuntos
Microbiologia de Alimentos , Filogenia , Pseudomonas/classificação , Carne Vermelha/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Bovinos , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Alemanha , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/químicaRESUMO
During a project focusing on the diversity of meat microbiota associated with beef ripening, a Pseudomonas strain was isolated exhibiting high 16S rRNA gene sequence similarities (>99â%) to Pseudomonas carnis DSM 107652T, P. lactis DSM 29167T, P. paralactis DSM 29164T and P. azotoformans DSM 18862T. Phylogenetic analysis of the complete rpoB gene sequences of the isolate V5/DAB/2/5T indicated a separate branch with about 99.0â% nucleotide identities to the closest relatives P. carnis DSM 107652T, P. lactis DSM 29167T and P. paralactis DSM 29164T, while average nucleotide identities (ANIb) calculated from the draft genomes were 94.8, 94.2 and 90.2â%, respectively. Pairwise genome-to-genome distance calculations (GGDC) resulted in values of 67.7, 63.5 and 45.7â%, respectively, lying below the actual species demarcation line as well. A second isolate, UBT403, was detected some years later by using matrix-assisted laser desorption ionization-time of flight MS of the microbiota of minced beef. The fatty acid profile of V5/DAB/2/5T consisted of C16â:â0, summed feature C 16â:â1 ω7c/iso-C15â:â0 2-OH, C18â:â1 ω7c, C17â:â0 cyclo, C12â:â0, C12â:â0 3-OH, C10â:â0 3-OH and C12â:â0 2-OH. The major cellular lipids were aminopholipids, phospholipids, phosphatidylethanolamine and phosphatidylglycerol; the major quinone was Q9 with a minor proportion of Q8. Based on phenotypic and chemotaxonomic characterizations, the isolates can be considered as representing a novel species, for which the name Pseudomonas paracarnis sp. nov. is proposed. The type strain is V5/DAB/2/5T (=DSM 111363T=LMG 31846T); a second strain is UBT403 (=DSM 111362=LMG 31847).
Assuntos
Microbiologia de Alimentos , Filogenia , Pseudomonas/classificação , Carne Vermelha/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Bovinos , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
Actinomycetes are known for producing diverse secondary metabolites. Combining genomics with untargeted data-dependent tandem MS and molecular networking, we characterized the secreted metabolome of the tunicamycin producer Streptomyces chartreusis NRRL 3882. The genome harbors 128 predicted biosynthetic gene clusters. We detected >1,000 distinct secreted metabolites in culture supernatants, only 22 of which were identified based on standards and public spectral libraries. S. chartreusis adapts the secreted metabolome to cultivation conditions. A number of metabolites are produced iron dependently, among them 17 desferrioxamine siderophores aiding in iron acquisition. Eight previously unknown members of this long-known compound class are described. A single desferrioxamine synthesis gene cluster was detected in the genome, yet different sets of desferrioxamines are produced in different media. Additionally, a polyether ionophore, differentially produced by the calcimycin biosynthesis cluster, was discovered. This illustrates that metabolite output of a single biosynthetic machine can be exquisitely regulated not only with regard to product quantity but also with regard to product range. Compared with chemically defined medium, in complex medium, total metabolite abundance was higher, structural diversity greater, and the average molecular weight almost doubled. Tunicamycins, for example, were only produced in complex medium. Extrapolating from this study, we anticipate that the larger part of bacterial chemistry, including chemical structures, ecological functions, and pharmacological potential, is yet to be uncovered.
Assuntos
Metaboloma/fisiologia , Sideróforos , Streptomyces/química , Streptomyces/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Desferroxamina/química , Desferroxamina/metabolismo , Redes e Vias Metabólicas , Metabolômica , Modelos Moleculares , Sideróforos/química , Sideróforos/metabolismoRESUMO
Marine sponges are prolific sources of unique bioactive natural products. The sponge Theonella swinhoei is represented by several distinct variants with largely nonoverlapping chemistry. For the Japanese chemotype Y harboring diverse complex polyketides and peptides, we previously provided genomic and functional evidence that a single symbiont, the filamentous, multicellular organism "Candidatus Entotheonella factor," produces almost all of these compounds. To obtain further insights into the chemistry of "Entotheonella," we investigated another phylotype, "Candidatus Entotheonella serta," present in the T. swinhoei WA sponge chemotype, a source of theonellamide- and misakinolide-type compounds. Unexpectedly, considering the lower chemical diversity, sequencing of individual bacterial filaments revealed an even larger number of biosynthetic gene regions than for Ca E. factor, with virtually no overlap. These included genes for misakinolide and theonellamide biosynthesis, the latter assigned by comparative genomic and metabolic analysis of a T. swinhoei chemotype from Israel, and by biochemical studies. The data suggest that both compound families, which were among the earliest model substances to study bacterial producers in sponges, originate from the same bacterium in T. swinhoei WA. They also add evidence that metabolic richness and variability could be a more general feature of Entotheonella symbionts.
Assuntos
Fenômenos Fisiológicos Bacterianos , Simbiose , Theonella/microbiologia , Animais , Bactérias/química , Bactérias/genética , Bactérias/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Genômica , Policetídeos/metabolismo , Theonella/química , Theonella/fisiologiaRESUMO
By culturing microorganisms under standard laboratory conditions, most biosynthetic gene clusters (BGCs) are not expressed, and thus, the products are not produced. To explore this biosynthetic potential, we developed a novel "semi-targeted" approach focusing on activating "silent" BGCs by concurrently introducing a group of regulator genes into streptomycetes of the Tübingen strain collection. We constructed integrative plasmids containing two classes of regulatory genes under the control of the constitutive promoter ermE*p (cluster situated regulators (CSR) and Streptomyces antibiotic regulatory proteins (SARPs)). These plasmids were introduced into Streptomyces sp. TÜ17, Streptomyces sp. TÜ10 and Streptomyces sp. TÜ102. Introduction of the CSRs-plasmid into strain S. sp. TÜ17 activated the production of mayamycin A. By using the individual regulator genes, we proved that Aur1P, was responsible for the activation. In strain S. sp. TÜ102, the introduction of the SARP-plasmid triggered the production of a chartreusin-like compound. Insertion of the CSRs-plasmid into strain S. sp. TÜ10 resulted in activating the warkmycin-BGC. In both recombinants, activation of the BGCs was only possible through the simultaneous expression of aur1PR3 and griR in S. sp. TÜ102 and aur1P and pntR in of S. sp. TÜ10.
Assuntos
Proteínas de Bactérias/genética , Benzo(a)Antracenos/metabolismo , Família Multigênica , Proteínas Recombinantes/genética , Streptomyces/genética , Proteínas de Bactérias/metabolismo , Benzopiranos , Regulação Bacteriana da Expressão Gênica , Glicosídeos/biossíntese , Regiões Promotoras Genéticas , Proteínas Recombinantes/metabolismo , Streptomyces/crescimento & desenvolvimento , Streptomyces/metabolismo , Fatores de Transcrição/metabolismo , Trissacarídeos/biossínteseRESUMO
Lignocellulose is one of the most abundant renewable carbon sources, representing an alternative to petroleum for the production of fuel and chemicals. Nonetheless, the lignocellulose saccharification process, to release sugars for downstream applications, is one of the most crucial factors economically challenging to its use. The synergism required among the various carbohydrate-active enzymes (CAZymes) for efficient lignocellulose breakdown is often not satisfactorily achieved with an enzyme mixture from a single strain. To overcome this challenge, enrichment strategies can be applied to develop microbial communities with an efficient CAZyme arsenal, incorporating complementary and synergistic properties, to improve lignocellulose deconstruction. We report a comprehensive and deep analysis of an enriched rumen anaerobic consortium (ERAC) established on sugarcane bagasse (SB). The lignocellulolytic abilities of the ERAC were confirmed by analyzing the depolymerization of bagasse by scanning electron microscopy, enzymatic assays, and mass spectrometry. Taxonomic analysis based on 16S rRNA sequencing elucidated the community enrichment process, which was marked by a higher abundance of Firmicutes and Synergistetes species. Shotgun metagenomic sequencing of the ERAC disclosed 41 metagenome-assembled genomes (MAGs) harboring cellulosomes and polysaccharide utilization loci (PULs), along with a high diversity of CAZymes. The amino acid sequences of the majority of the predicted CAZymes (60% of the total) shared less than 90% identity with the sequences found in public databases. Additionally, a clostridial MAG identified in this study produced proteins during consortium development with scaffoldin domains and CAZymes appended to dockerin modules, thus representing a novel cellulosome-producing microorganism.IMPORTANCE The lignocellulolytic ERAC displays a unique set of plant polysaccharide-degrading enzymes (with multimodular characteristics), cellulosomal complexes, and PULs. The MAGs described here represent an expansion of the genetic content of rumen bacterial genomes dedicated to plant polysaccharide degradation, therefore providing a valuable resource for the development of biocatalytic toolbox strategies to be applied to lignocellulose-based biorefineries.
Assuntos
Bactérias Anaeróbias/metabolismo , Proteínas de Bactérias/metabolismo , Celulossomas/metabolismo , Microbioma Gastrointestinal , Lignina/metabolismo , Consórcios Microbianos , Polissacarídeos/metabolismo , Animais , Bactérias Anaeróbias/enzimologia , Celulases/metabolismo , Celulose , Rúmen/microbiologia , SaccharumRESUMO
Streptomyces strains are well known as promising source of bioactive secondary metabolites, important in ecology, biotechnology and medicine. In this study, we present the draft genome of the new type strain Streptomyces tunisialbus DSM 105760T (= JCM 32165T), a rhizospheric bacterium with antimicrobial activity. The genome is 6,880,753 bp in size (average GC content, 71.85%) and encodes 5802 protein-coding genes. Preliminary analysis with antiSMASH 5.1.2. reveals 34 predicted gene clusters for the synthesis of potential secondary metabolites, which was compared with those of Streptomyces varsoviensis NRRL ISP-5346.
Assuntos
Genoma Bacteriano/genética , Streptomyces/genética , Composição de Bases , Sequência de BasesRESUMO
Two Pseudomonas isolates derived independently from raw refrigerated processing meat of bovine origin intended for the manufacture of Bologna-type cooked sausage could be distinguished from other known species in subsequent phylogenetic analyses. Comparison of the complete rpoB gene sequences in combination with nearly complete 16S rRNA gene sequences revealed a separate branch within the Pseudomonas fragi group. In further analyses, comprising phenotypic and chemotaxonomic characterization as well as average nucleotide identity (ANI) values obtained from the draft genome assemblies, the two isolates could be distinguished from all so far published closely related species. The closest relative was P. fragi DSM 3456T with ANI values of about 90.2â%. Other close Pseudomonas neighbours were P. psychrophila DSM 17535T (86.5â%), P. deceptionensis DSM 26521T (86.4â%), P. versuta DSM 101070T (83.8â%), P. taetrolens DSM 21104T (83.2â%), P. weihenstephanensis DSM 29166T (82.3â%), P. helleri DSM 29165T (82.7â%) and P. lundensis DSM 6252T (81.9â%). The G+C contents of isolates TH39T and TH26 were both 58.2 mol%. The major cellular lipids of strain TH39T were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol; the major quinone was Q9 with small amounts of Q8. Based on these data, the isolates TH39T and TH26 (=DSM 107389=LMG 30831) represent a novel species within the genus Pseudomonas , for which the name Pseudomonas bubulae sp. nov. is proposed. The type strain is TH39T (=DSM 107390T=LMG 30830T).
Assuntos
Filogenia , Pseudomonas/classificação , Carne Vermelha/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Bovinos , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/químicaRESUMO
During investigations of spoilage-associated meat microbiota, Pseudomonas isolates were found in two different laboratories showing highest similarities to Pseudomonas lactis DSM 29167T, Pseudomonas paralactis DSM 29164T and Pseudomonas azotoformans DSM 18862T based on 16S rRNA gene sequence comparisons. Phylogenetic analysis of the complete rpoB gene sequences of isolates B4-1T and SpeckC indicated a separate branch with 99.0 and 99.1â% identity, respectively, to their closest relative (P. lactis DSM 29167T). Further phenotypic and chemotaxonomic characterizations, as well as average nucleotide identity (ANIb) values obtained from the draft genomes, revealed that these isolates could be considered as representing a novel species, with ANIb values of around 94 and 90â% with their closest relatives P. lactis and P. paralactis. Other related species showed ANIb values below 90â%, including Pseudomonas libanensis DSM 17149T, Pseudomonas synxantha DSM 18928T, Pseudomonas orientalis DSM 17489T, Pseudomonas veronii DSM 11331T and P. azotoformans DSM 18862T. Genome-to-genome distance calculations between B4-1T and its closest relative, P. lactis DSM 29167T, showed 62.6â% relatedness. The G+C contents of B4-1T and SpeckC were 59.8 and 59.9 mol%, respectively. The major cellular lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol; the major quinone was Q9. Based on these data, the new species Pseudomonas carnis sp. nov. is proposed, the type strain is B4-1T (=DSM 107652T=LMG 30892T); a second strain is SpeckC (=DSM 107651=LMG 30893).
Assuntos
Microbiologia de Alimentos , Carne/microbiologia , Filogenia , Pseudomonas/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Alemanha , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Aves Domésticas , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Suínos , Ubiquinona/químicaRESUMO
Tropolone sesquiterpenoids (TS) are an intriguing family of biologically active fungal meroterpenoids that arise through a unique intermolecular hetero Diels-Alder (hDA) reaction between humulene and tropolones. Here, we report on the combinatorial biosynthesis of a series of unprecedented analogs of the TS pycnidione 1 and xenovulene A 2. In a systematic synthetic biology driven approach, we recombined genes from three TS biosynthetic gene clusters (pycnidione 1, xenovulene A 2 and eupenifeldin 3) in the fungal host Aspergillus oryzae NSAR1. Rational design of the reconstituted pathways granted control over the number of hDA reactions taking place, the chemical nature of the fused polyketide moiety (tropolono- vs. monobenzo-pyranyl) and the degree of hydroxylation. Formation of unexpected monobenzopyranyl sesquiterpenoids was investigated using isotope-feeding studies to reveal a new and highly unusual oxidative ring contraction rearrangement.