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1.
Mol Ecol ; : e17437, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38887167

RESUMEN

Environmental stress is a fundamental facet of life and a significant driver of natural selection in the wild. Gene expression diversity may facilitate adaptation to environmental changes, without necessary genetic change, but its role in adaptive divergence remains largely understudied in Neotropical systems. In Amazonian riparian forests, species distribution is predominantly influenced by species' waterlogging tolerance. The flooding gradient delineates distinct wetland forest types, shaping habitats and species characteristics. Here we investigated the molecular basis of environmental stress response in a tropical ground-herb species (Ischnosiphon puberulus) to environmental variation in Amazonian riparian forests. We compared environmental variables and gene expression profiles from individuals collected in two forest types: Igapó and Terra firme in the Amazonian riparian forests. Predictable seasonal flooding poses a significant challenge in Igapó compared to Terra firme environments, with the former presenting higher water column height and longer flooding duration. Our findings suggest that contrasting environmental conditions related to flooding regimes are important drivers of population genetic differentiation and differential gene expression in I. puberulus. Enriched gene ontology terms highlight associations with environmental stresses, such as defence response, water transport, phosphorylation, root development, response to auxin, salicylic acid and oxidative stress. By uncovering key environmental stress response pathways conserved across populations, I. puberulus offers novel genetic insights into the molecular basis of plant reactions to environmental constraints found in flooded areas of this highly biodiverse neotropical ecosystem.

2.
Funct Integr Genomics ; 23(2): 101, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36964864

RESUMEN

Biodiversity is proposed as a sustainable alternative for the economic development of high-biodiversity regions. Especially in the field of biodiversity genomics, the development of low-cost DNA sequencing opens an opportunity for new actors beyond academia to engage in genomic sequencing. However, it is challenging to adequately compensate non-academic actors such as local populations for their contribution to the innovation process, preventing better bioeconomy development. Although many repositories register genomic data to support biodiversity research, they do not facilitate the fair sharing of economic benefits. In this work, we propose the creation of the Amazon Biobank, a community-based genetic database. We employed blockchain to build a transparent and verifiable log of transactions involving genomic data, and we used smart contracts to implement an internal monetary system for all participants who collect, insert, process, store, and validate genomic data. We also used peer-to-peer solutions to allow users with commodity computers to collaborate with the storage and distribution of DNA files. By combining emerging technologies, Amazon Biobank provides adequate benefit-sharing among all participants that collaborate with data, knowledge, and computational resources. It also provides traceability and auditability, allowing easy association between biotechnological research and DNA data. In addition, the solution is highly scalable and less dependent on the trust deposited in any system player. Therefore, Amazon Biobank can become an important stepping stone to unlock the potential of bioeconomy in rich ecosystems such as the Amazon Rainforest.


Asunto(s)
Bancos de Muestras Biológicas , Ecosistema , Humanos , Genómica , Bases de Datos Genéticas , ADN
3.
Mol Genet Genomics ; 297(5): 1403-1421, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35879567

RESUMEN

KEY MESSAGE: Nitrate uptake in sugarcane roots is regulated at the transcriptional and posttranscriptional levels based on the physiological status of the plant and is likely a determinant mechanism for discrimination against nitrate. Sugarcane (Saccharum spp.) is one of the most suitable energy crops for biofuel feedstock, but the reduced recovery of nitrogen (N) fertilizer by sugarcane roots increases the crop carbon footprint. The low nitrogen use efficiency (NUE) of sugarcane has been associated with the significantly low nitrate uptake, which limits the utilization of the large amount of nitrate available in agricultural soils. To understand the regulation of nitrate uptake in sugarcane roots, we identified the major canonical nitrate transporter genes (NRTs-NITRATE TRANSPORTERS) and then determined their expression profiles in roots under contrasting N conditions. Correlation of gene expression with 15N-nitrate uptake revealed that under N deprivation or inorganic N (ammonium or nitrate) supply in N-sufficient roots, the regulation of ScNRT2.1 and ScNRT3.1 expression is the predominant mechanism for the modulation of the activity of the nitrate high-affinity transport system. Conversely, in N-deficient roots, the induction of ScNRT2.1 and ScNRT3.1 transcription is not correlated with the marked repression of nitrate uptake in response to nitrate resupply or high N provision, which suggested the existence of a posttranscriptional regulatory mechanism. Our findings suggested that high-affinity nitrate uptake is regulated at the transcriptional and presumably at the posttranscriptional levels based on the physiological N status and that the regulation of NRT2.1 and NRT3.1 activity is likely a determinant mechanism for the discrimination against nitrate uptake observed in sugarcane roots, which contributes to the low NUE in this crop species.


Asunto(s)
Saccharum , Productos Agrícolas , Regulación de la Expresión Génica de las Plantas , Nitratos , Nitrógeno , Raíces de Plantas
4.
J Exp Bot ; 73(11): 3651-3670, 2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35176760

RESUMEN

Witches' broom disease of cacao is caused by the pathogenic fungus Moniliophthora perniciosa. By using tomato (Solanum lycopersicum) cultivar Micro-Tom (MT) as a model system, we investigated the physiological and metabolic consequences of M. perniciosa infection to determine whether symptoms result from sink establishment during infection. Infection of MT by M. perniciosa caused reductions in root biomass and fruit yield, a decrease in leaf gas exchange, and down-regulation of photosynthesis-related genes. The total leaf area and water potential decreased, while ABA levels, water conductance/conductivity, and ABA-related gene expression increased. Genes related to sugar metabolism and those involved in secondary cell wall deposition were up-regulated upon infection, and the concentrations of sugars, fumarate, and amino acids increased. 14C-glucose was mobilized towards infected MT stems, but not in inoculated stems of the MT line overexpressing CYTOKININ OXIDASE-2 (35S::AtCKX2), suggesting a role for cytokinin in establishing a sugar sink. The up-regulation of genes involved in cell wall deposition and phenylpropanoid metabolism in infected MT, but not in 35S::AtCKX2 plants, suggests establishment of a cytokinin-mediated sink that promotes tissue overgrowth with an increase in lignin. Possibly, M. perniciosa could benefit from the accumulation of secondary cell walls during its saprotrophic phase of infection.


Asunto(s)
Agaricales , Cacao , Solanum lycopersicum , Agaricales/genética , Cacao/genética , Pared Celular , Citocininas , Solanum lycopersicum/genética , Solanum lycopersicum/microbiología , Enfermedades de las Plantas/microbiología , Azúcares , Agua
5.
Int J Mol Sci ; 23(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36430425

RESUMEN

Antifolates such as methotrexate (MTX) have been largely known as anticancer agents because of their role in blocking nucleic acid synthesis and cell proliferation. Their mechanism of action lies in their ability to inhibit enzymes involved in the folic acid cycle, especially human dihydrofolate reductase (hDHFR). However, most of them have a classical structure that has proven ineffective against melanoma, and, therefore, inhibitors with a non-classical lipophilic structure are increasingly becoming an attractive alternative to circumvent this clinical resistance. In this study, we conducted a protocol combining virtual screening (VS) and cell-based assays to identify new potential non-classical hDHFR inhibitors. Among 173 hit compounds identified (average logP = 3.68; average MW = 378.34 Da), two-herein, called C1 and C2-exhibited activity against melanoma cell lines B16 and A375 by MTT and Trypan-Blue assays. C1 showed cell growth arrest (39% and 56%) and C2 showed potent cytotoxic activity (77% and 51%) in a dose-dependent manner. The effects of C2 on A375 cell viability were greater than MTX (98% vs 60%) at equivalent concentrations and times. Our results indicate that the integrated in silico/in vitro approach provided a benchmark to identify novel promising non-classical DHFR inhibitors showing activity against melanoma cells.


Asunto(s)
Antineoplásicos , Antagonistas del Ácido Fólico , Melanoma , Humanos , Antagonistas del Ácido Fólico/farmacología , Antagonistas del Ácido Fólico/química , Tetrahidrofolato Deshidrogenasa/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Melanoma/tratamiento farmacológico , Metotrexato/farmacología
6.
Genet Mol Biol ; 45(1): e50510051, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35037932

RESUMEN

Pseudocercospora ulei is the causal agent of South American Leaf Blight (SALB), the main disease affecting Hevea brasiliensis rubber tree, a native species to the Amazon. Rubber tree is a major crop in South American countries and SALB disease control strategies would benefit from the availability of genomic resources for the fungal pathogen. Here, we assembled and annotated the P. ulei genome. Shotgun sequencing was performed using second and third generation sequencing technologies. We present the first P. ulei high-quality genome assembly, the largest among Mycosphaerellaceae, with 93.8 Mbp, comprising 215 scaffolds, an N50 of 2.8 Mbp and a BUSCO gene completeness of 97.5%. We identified 12,745 protein-coding gene models in the P. ulei genome with 756 genes encoding secreted proteins and 113 genes encoding effector candidates. Most of the genome (80%) is composed of repetitive elements dominated by retrotransposons of the Gypsy superfamily. P. ulei has the largest genome size among Mycosphaerellaceae, with the highest TE content. In conclusion, we have established essential genomic resources for a wide range of studies on P. ulei and related species.

7.
Genet Mol Biol ; 43(3): e20190122, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32511662

RESUMEN

Wickerhamomyces anomalus LBCM1105 is a yeast isolated from cachaça distillery fermentation vats, notable for exceptional glycerol consumption ability. We report its draft genome with 20.5x in-depth coverage and around 90% extension and completeness. It harbors the sequences of proteins involved in glycerol transport and metabolism.

8.
BMC Biotechnol ; 19(1): 41, 2019 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-31253157

RESUMEN

BACKGROUND: Pythium irregulare is an oleaginous Oomycete able to accumulate large amounts of lipids, including Eicosapentaenoic acid (EPA). EPA is an important and expensive dietary supplement with a promising and very competitive market, which is dependent on fish-oil extraction. This has prompted several research groups to study biotechnological routes to obtain specific fatty acids rather than a mixture of various lipids. Moreover, microorganisms can use low cost carbon sources for lipid production, thus reducing production costs. Previous studies have highlighted the production of EPA by P. irregulare, exploiting diverse low cost carbon sources that are produced in large amounts, such as vinasse, glycerol, and food wastewater. However, there is still a lack of knowledge about its biosynthetic pathways, because no functional annotation of any Pythium sp. exists yet. The goal of this work was to identify key genes and pathways related to EPA biosynthesis, in P. irregulare CBS 494.86, by sequencing and performing an unprecedented annotation of its genome, considering the possibility of using wastewater as a carbon source. RESULTS: Genome sequencing provided 17,727 candidate genes, with 3809 of them associated with enzyme code and 945 with membrane transporter proteins. The functional annotation was compared with curated information of oleaginous organisms, understanding amino acids and fatty acids production, and consumption of carbon and nitrogen sources, present in the wastewater. The main features include the presence of genes related to the consumption of several sugars and candidate genes of unsaturated fatty acids production. CONCLUSIONS: The whole metabolic genome presented, which is an unprecedented reconstruction of P. irregulare CBS 494.86, shows its potential to produce value-added products, in special EPA, for food and pharmaceutical industries, moreover it infers metabolic capabilities of the microorganism by incorporating information obtained from literature and genomic data, supplying information of great importance to future work.


Asunto(s)
Ácido Eicosapentaenoico/biosíntesis , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Genoma Fúngico/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Pythium/genética , Suplementos Dietéticos , Proteínas Fúngicas/metabolismo , Microbiología Industrial/métodos , Pythium/metabolismo
9.
Cell Microbiol ; 19(4)2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27706915

RESUMEN

Invasive aspergillosis is predominantly caused by Aspergillus fumigatus, and adaptations to stresses experienced within the human host are a prerequisite for the survival and virulence strategies of the pathogen. The central signal transduction pathway operating during hyperosmotic stress is the high osmolarity glycerol mitogen-activated protein kinase cascade. A. fumigatus MpkC and SakA, orthologues of the Saccharomyces cerevisiae Hog1p, constitute the primary regulator of the hyperosmotic stress response. We compared A. fumigatus wild-type transcriptional response to osmotic stress with the ΔmpkC, ΔsakA, and ΔmpkC ΔsakA strains. Our results strongly indicate that MpkC and SakA have independent and collaborative functions during the transcriptional response to transient osmotic stress. We have identified and characterized null mutants for four A. fumigatus basic leucine zipper proteins transcription factors. The atfA and atfB have comparable expression levels with the wild-type in ΔmpkC but are repressed in ΔsakA and ΔmpkC ΔsakA post-osmotic stress. The atfC and atfD have reduced expression levels in all mutants post-osmotic stress. The atfA-D null mutants displayed several phenotypes related to osmotic, oxidative, and cell wall stresses. The ΔatfA and ΔatfB were shown to be avirulent and to have attenuated virulence, respectively, in both Galleria mellonella and a neutropenic murine model of invasive pulmonary aspergillosis.


Asunto(s)
Aspergilosis/microbiología , Aspergillus fumigatus/enzimología , Proteínas Fúngicas/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Transcriptoma , Animales , Aspergillus fumigatus/genética , Pared Celular , Femenino , Proteínas Fúngicas/metabolismo , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , Ontología de Genes , Genoma Fúngico , Ratones Endogámicos BALB C , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Presión Osmótica , Transducción de Señal , Estrés Fisiológico , Factores de Transcripción/fisiología
10.
Cell Microbiol ; 19(12)2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28753224

RESUMEN

Metal restriction imposed by mammalian hosts during an infection is a common mechanism of defence to reduce or avoid the pathogen infection. Metals are essential for organism survival due to its involvement in several biological processes. Aspergillus fumigatus causes invasive aspergillosis, a disease that typically manifests in immunocompromised patients. A. fumigatus PpzA, the catalytic subunit of protein phosphatase Z (PPZ), has been recently identified as associated with iron assimilation. A. fumigatus has 2 high-affinity mechanisms of iron acquisition during infection: reductive iron assimilation and siderophore-mediated iron uptake. It has been shown that siderophore production is important for A. fumigatus virulence, differently to the reductive iron uptake system. Transcriptomic and proteomic comparisons between ∆ppzA and wild-type strains under iron starvation showed that PpzA has a broad influence on genes involved in secondary metabolism. Liquid chromatography-mass spectrometry under standard and iron starvation conditions confirmed that the ΔppzA mutant had reduced production of pyripyropene A, fumagillin, fumiquinazoline A, triacetyl-fusarinine C, and helvolic acid. The ΔppzA was shown to be avirulent in a neutropenic murine model of invasive pulmonary aspergillosis. PpzA plays an important role at the interface between iron starvation, regulation of SM production, and pathogenicity in A. fumigatus.


Asunto(s)
Aspergillus fumigatus/enzimología , Aspergillus fumigatus/patogenicidad , Hierro/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Metabolismo Secundario , Animales , Aspergillus fumigatus/genética , Aspergillus fumigatus/metabolismo , Cromatografía Liquida , Modelos Animales de Enfermedad , Eliminación de Gen , Perfilación de la Expresión Génica , Aspergilosis Pulmonar Invasiva/microbiología , Aspergilosis Pulmonar Invasiva/patología , Espectrometría de Masas , Metabolómica , Ratones , Fosfoproteínas Fosfatasas/genética , Proteoma/análisis , Virulencia
11.
Mol Microbiol ; 102(4): 642-671, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27538790

RESUMEN

The serine-threonine kinase TOR, the Target of Rapamycin, is an important regulator of nutrient, energy and stress signaling in eukaryotes. Sch9, a Ser/Thr kinase of AGC family (the cAMP-dependent PKA, cGMP- dependent protein kinase G and phospholipid-dependent protein kinase C family), is a substrate of TOR. Here, we characterized the fungal opportunistic pathogen Aspergillus fumigatus Sch9 homologue (SchA). The schA null mutant was sensitive to rapamycin, high concentrations of calcium, hyperosmotic stress and SchA was involved in iron metabolism. The ΔschA null mutant showed increased phosphorylation of SakA, the A. fumigatus Hog1 homologue. The schA null mutant has increased and decreased trehalose and glycerol accumulation, respectively, suggesting SchA performs different roles for glycerol and trehalose accumulation during osmotic stress. The schA was transcriptionally regulated by osmotic stress and this response was dependent on SakA and MpkC. The double ΔschA ΔsakA and ΔschA ΔmpkC mutants were more sensitive to osmotic stress than the corresponding parental strains. Transcriptomics and proteomics identified direct and indirect targets of SchA post-exposure to hyperosmotic stress. Finally, ΔschA was avirulent in a low dose murine infection model. Our results suggest there is a complex network of interactions amongst the A. fumigatus TOR, SakA and SchA pathways.


Asunto(s)
Aspergillus fumigatus/enzimología , Aspergillus fumigatus/patogenicidad , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Animales , Aspergilosis/microbiología , Aspergillus fumigatus/metabolismo , Femenino , Proteínas Fúngicas/metabolismo , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Endogámicos BALB C , Presión Osmótica/fisiología , Estrés Oxidativo/genética , Estrés Oxidativo/fisiología , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Sirolimus/farmacología , Esporas Fúngicas/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Virulencia
12.
Genomics ; 101(4): 249-55, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23402767

RESUMEN

The main objective of the present study was to reanalyse tomato expression data that was previously submitted to the Tomato Expression Database to dissect the resistance/defence genomic and metabolic responses of tomato to Phytophthora infestans under field conditions. Overrepresented gene sets belonging to chromosome 10 were identified using the Gene Set Enrichment Analysis, and we found that these genes tend to be located towards the end of the chromosome 10. An analysis of syntenic regions between Arabidopsis thaliana chromosomes and the tomato chromosome 10 allowed us to identify conserved regions in the two genomes. In addition to allowing for the identification of tomato candidate genes participating in resistance/defence in the field, this approach allowed us to investigate the relationships of the candidate genes with chromosomal position and participation in metabolic functions, thus offering more insight into the phenomena occurring during the infection process.


Asunto(s)
Cromosomas de las Plantas/genética , Resistencia a la Enfermedad/genética , Genes de Plantas , Phytophthora infestans , Solanum lycopersicum/genética , Arabidopsis/genética , Secuencia Conservada , Bases de Datos Genéticas , Solanum lycopersicum/metabolismo , Solanum lycopersicum/microbiología , Familia de Multigenes , Sintenía
13.
J Integr Plant Biol ; 56(6): 527-38, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24373132

RESUMEN

The control of gene expression by transcriptional regulators and other types of functionally relevant DNA transactions such as chromatin remodeling and replication underlie a vast spectrum of biological processes in all organisms. DNA transactions require the controlled interaction of proteins with DNA sequence motifs which are often located in nucleosome-depleted regions (NDRs) of the chromatin. Formaldehyde-assisted isolation of regulatory elements (FAIRE) has been established as an easy-to-implement method for the isolation of NDRs from a number of eukaryotic organisms, and it has been successfully employed for the discovery of new regulatory segments in genomic DNA from, for example, yeast, Drosophila, and humans. Until today, however, FAIRE has only rarely been employed in plant research and currently no detailed FAIRE protocol for plants has been published. Here, we provide a step-by-step FAIRE protocol for NDR discovery in Arabidopsis thaliana. We demonstrate that NDRs isolated from plant chromatin are readily amenable to quantitative polymerase chain reaction and next-generation sequencing. Only minor modification of the FAIRE protocol will be needed to adapt it to other plants, thus facilitating the global inventory of regulatory regions across species.


Asunto(s)
Arabidopsis/genética , ADN de Plantas/aislamiento & purificación , Formaldehído/farmacología , Biología Molecular/métodos , Secuencias Reguladoras de Ácidos Nucleicos/genética , Arabidopsis/efectos de los fármacos , Cromosomas de las Plantas/genética , ADN de Plantas/genética , Genes Esenciales , Genoma de Planta/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Reacción en Cadena de la Polimerasa , Sonicación
14.
Proteomics ; 12(1): 95-100, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22065562

RESUMEN

Nuclear proteins play a central role in regulating gene expression. Their identification is important for understanding how the nuclear repertoire changes over time under different conditions. Nuclear proteins are often underrepresented in proteomic studies due to the frequently low abundance of proteins involved in regulatory processes. So far, only few studies describing the nuclear proteome of plant species have been published. Recently, the genome sequence of the unicellular green alga Chlamydomonas reinhardtii has been obtained and annotated, allowing the development of further detailed studies for this organism. However, a detailed description of its nuclear proteome has not been reported so far. Here, we present an analysis of the nuclear proteome of the sequenced Chlamydomonas strain cc503. Using LC-MS/MS, we identified 672 proteins from nuclei isolates with a maximum 1% peptide spectrum false discovery rate. Besides well-known proteins (e.g. histones), transcription factors and other transcriptional regulators (e.g. tubby and HMG) were identified. The presence of protein motifs in nuclear proteins was investigated by computational tools, and specific over-represented protein motifs were identified. This study provides new insights into the complexity of the nuclear environment and reveals novel putative protein targets for further studies of nuclear mechanisms.


Asunto(s)
Núcleo Celular/metabolismo , Chlamydomonas reinhardtii/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Proteínas de Plantas/química , Proteoma/química , Espectrometría de Masas en Tándem
15.
PeerJ ; 7: e7558, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31579570

RESUMEN

BACKGROUND: Chloroplast genomes provide insufficient phylogenetic information to distinguish between closely related sugarcane cultivars, due to the recent origin of many cultivars and the conserved sequence of the chloroplast. In comparison, the mitochondrial genome of plants is much larger and more plastic and could contain increased phylogenetic signals. We assembled a consensus reference mitochondrion with Illumina TruSeq synthetic long reads and Oxford Nanopore Technologies MinION long reads. Based on this assembly we also analyzed the mitochondrial transcriptomes of sugarcane and sorghum and improved the annotation of the sugarcane mitochondrion as compared with other species. METHODS: Mitochondrial genomes were assembled from genomic read pools using a bait and assemble methodology. The mitogenome was exhaustively annotated using BLAST and transcript datasets were mapped with HISAT2 prior to analysis with the Integrated Genome Viewer. RESULTS: The sugarcane mitochondrion is comprised of two independent chromosomes, for which there is no evidence of recombination. Based on the reference assembly from the sugarcane cultivar SP80-3280 the mitogenomes of four additional cultivars (R570, LCP85-384, RB72343 and SP70-1143) were assembled (with the SP70-1143 assembly utilizing both genomic and transcriptomic data). We demonstrate that the sugarcane plastome is completely transcribed and we assembled the chloroplast genome of SP80-3280 using transcriptomic data only. Phylogenomic analysis using mitogenomes allow closely related sugarcane cultivars to be distinguished and supports the discrimination between Saccharum officinarum and Saccharum cultum as modern sugarcane's female parent. From whole chloroplast comparisons, we demonstrate that modern sugarcane arose from a limited number of Saccharum cultum female founders. Transcriptomic and spliceosomal analyses reveal that the two chromosomes of the sugarcane mitochondrion are combined at the transcript level and that splice sites occur more frequently within gene coding regions than without. We reveal one confirmed and one potential cytoplasmic male sterility (CMS) factor in the sugarcane mitochondrion, both of which are transcribed. CONCLUSION: Transcript processing in the sugarcane mitochondrion is highly complex with diverse splice events, the majority of which span the two chromosomes. PolyA baited transcripts are consistent with the use of polyadenylation for transcript degradation. For the first time we annotate two CMS factors within the sugarcane mitochondrion and demonstrate that sugarcane possesses all the molecular machinery required for CMS and rescue. A mechanism of cross-chromosomal splicing based on guide RNAs is proposed. We also demonstrate that mitogenomes can be used to perform phylogenomic studies on sugarcane cultivars.

16.
Biotechnol Biofuels ; 10: 254, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29118851

RESUMEN

BACKGROUND: Using globally abundant crop residues as a carbon source for energy generation and renewable chemicals production stand out as a promising solution to reduce current dependency on fossil fuels. In nature, such as in compost habitats, microbial communities efficiently degrade the available plant biomass using a diverse set of synergistic enzymes. However, deconstruction of lignocellulose remains a challenge for industry due to recalcitrant nature of the substrate and the inefficiency of the enzyme systems available, making the economic production of lignocellulosic biofuels difficult. Metatranscriptomic studies of microbial communities can unveil the metabolic functions employed by lignocellulolytic consortia and identify novel biocatalysts that could improve industrial lignocellulose conversion. RESULTS: In this study, a microbial community from compost was grown in minimal medium with sugarcane bagasse sugarcane bagasse as the sole carbon source. Solid-state nuclear magnetic resonance was used to monitor lignocellulose degradation; analysis of metatranscriptomic data led to the selection and functional characterization of several target genes, revealing the first glycoside hydrolase from Carbohydrate Active Enzyme family 11 with exo-1,4-ß-xylanase activity. The xylanase crystal structure was resolved at 1.76 Å revealing the structural basis of exo-xylanase activity. Supplementation of a commercial cellulolytic enzyme cocktail with the xylanase showed improvement in Avicel hydrolysis in the presence of inhibitory xylooligomers. CONCLUSIONS: This study demonstrated that composting microbiomes continue to be an excellent source of biotechnologically important enzymes by unveiling the diversity of enzymes involved in in situ lignocellulose degradation.

17.
Sci Rep ; 7: 45073, 2017 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-28361917

RESUMEN

One of the drawbacks during second-generation biofuel production from plant lignocellulosic biomass is the accumulation of glucose, the preferred carbon source of microorganisms, which causes the repression of hydrolytic enzyme secretion by industrially relevant filamentous fungi. Glucose sensing, subsequent transport and cellular signalling pathways have been barely elucidated in these organisms. This study therefore characterized the transcriptional response of the filamentous fungus Aspergillus nidulans to the presence of high and low glucose concentrations under continuous chemostat cultivation with the aim to identify novel factors involved in glucose sensing and signalling. Several transcription factor- and transporter-encoding genes were identified as being differentially regulated, including the previously characterized glucose and xylose transporter HxtB. HxtB was confirmed to be a low affinity glucose transporter, localizing to the plasma membrane under low- and high-glucose conditions. Furthermore, HxtB was shown to be involved in conidiation-related processes and may play a role in downstream glucose signalling. A gene predicted to encode the protein kinase PskA was also identified as being important for glucose metabolism. This study identified several proteins with predicted roles in glucose metabolic processes and provides a foundation for further investigation into the response of biotechnologically important filamentous fungi to glucose.


Asunto(s)
Aspergillus nidulans/metabolismo , Metabolismo de los Hidratos de Carbono , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Glucosa/metabolismo , Transducción de Señal , Aspergillus nidulans/efectos de los fármacos , Aspergillus nidulans/genética , Metabolismo de los Hidratos de Carbono/genética , Biología Computacional/métodos , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Eliminación de Gen , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Ontología de Genes , Glucosa/farmacología , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Fenotipo , Unión Proteica , Transporte de Proteínas , Transducción de Señal/efectos de los fármacos , Transcripción Genética , Proteínas ras/metabolismo
18.
Front Plant Sci ; 7: 43, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26904035

RESUMEN

The development of microalgae sustainable applications needs better understanding of microalgae biology. Moreover, how cells coordinate their metabolism toward biomass accumulation is not fully understood. In this present study, flux balance analysis (FBA) was performed to identify sensitive metabolic pathways of Chlamydomonas reinhardtii under varied CO2 inputs. The metabolic network model of Chlamydomonas was updated based on the genome annotation data and sensitivity analysis revealed CO2 sensitive reactions. Biological experiments were performed with cells cultivated at 0.04% (air), 2.5, 5, 8, and 10% CO2 concentration under controlled conditions and cell growth profiles and biomass content were measured. Pigments, lipids, proteins, and starch were further quantified for the reference low (0.04%) and high (10%) CO2 conditions. The expression level of candidate genes of sensitive reactions was measured and validated by quantitative real time PCR. The sensitive analysis revealed mitochondrial compartment as the major affected by changes on the CO2 concentrations and glycolysis/gluconeogenesis, glyoxylate, and dicarboxylate metabolism among the affected metabolic pathways. Genes coding for glycerate kinase (GLYK), glycine cleavage system, H-protein (GCSH), NAD-dependent malate dehydrogenase (MDH3), low-CO2 inducible protein A (LCIA), carbonic anhydrase 5 (CAH5), E1 component, alpha subunit (PDC3), dual function alcohol dehydrogenase/acetaldehyde dehydrogenase (ADH1), and phosphoglucomutase (GPM2), were defined, among other genes, as sensitive nodes in the metabolic network simulations. These genes were experimentally responsive to the changes in the carbon fluxes in the system. We performed metabolomics analysis using mass spectrometry validating the modulation of carbon dioxide responsive pathways and metabolites. The changes on CO2 levels mostly affected the metabolism of amino acids found in the photorespiration pathway. Our updated metabolic network was compared to previous model and it showed more consistent results once considering the experimental data. Possible roles of the sensitive pathways in the biomass metabolism are discussed.

19.
Genome Announc ; 3(3)2015 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-25977443

RESUMEN

Here, we present the draft genome sequence of Thermus filiformis strain ATCC 43280, a thermophile bacterium capable of producing glycosylated carotenoids acylated with branched fatty acids and enzymes of biotechnological potential.

20.
Genome Announc ; 3(6)2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26634755

RESUMEN

Here, we present the draft genome sequence of Komagataeibacter intermedius strain AF2, which was isolated from Kombucha tea and is capable of producing cellulose, although at lower levels compared to another bacterium from the same environment, K. rhaeticus strain AF1.

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