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1.
Cureus ; 16(1): e51971, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38333478

RESUMEN

Rosette-forming glioneuronal tumor (RGNT) is a rare and indolent mixed glioneuronal tumor involving primarily the fourth ventricular region and occurring predominantly in young adults. We present a case of a 44-year-old woman presented with progressive headaches, vomiting, and a sudden decreasing level of consciousness. The magnetic resonance imaging showed a regular lesion within the anterior portion of the third ventricle and the patient underwent an endoscopic approach to remove the tumor that was exclusively within the anterior portion of the third ventricle. Histopathology showed an RGNT that was totally removed. We also report some unusual complications that are described in the literature and are related to ventricular endoscopy such as seizures and hydroelectrolyte disorders. With two years of follow-up, the patient had no complaints and no tumor progression was observed.

2.
JPRAS Open ; 39: 152-156, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38269256

RESUMEN

Skull osteoradionecrosis may happen after radiation therapy for head and neck cancer. Here in, the authors present a case of intracranial carcinoma with osteoradionecrosis and exposure of frontal bone with a large communication between nasal cavity and anterior fossa associated. The patient was successfully treated with resection of the tumor and reconstruction omentum free flap wrapped around autologous bone graft.

3.
New Phytol ; 241(1): 409-429, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37953378

RESUMEN

The emergence of new pathogens is an ongoing threat to human health and agriculture. While zoonotic spillovers received considerable attention, the emergence of crop diseases is less well studied. Here, we identify genomic factors associated with the emergence of Pseudomonas syringae bacterial blight of coffee. Fifty-three P. syringae strains from diseased Brazilian coffee plants were sequenced. Comparative and evolutionary analyses were used to identify loci associated with coffee blight. Growth and symptomology assays were performed to validate the findings. Coffee isolates clustered in three lineages, including primary phylogroups PG3 and PG4, and secondary phylogroup PG11. Genome-wide association study of the primary PG strains identified 37 loci, including five effectors, most of which were encoded on a plasmid unique to the PG3 and PG4 coffee strains. Evolutionary analyses support the emergence of coffee blight in PG4 when the coffee-associated plasmid and associated effectors derived from a divergent plasmid carried by strains associated with other hosts. This plasmid was only recently transferred into PG3. Natural diversity and CRISPR-Cas9 plasmid curing were used to show that strains with the coffee-associated plasmid grow to higher densities and cause more severe disease symptoms in coffee. This work identifies possible evolutionary mechanisms underlying the emergence of a new lineage of coffee pathogens.


Asunto(s)
Genoma Bacteriano , Pseudomonas syringae , Humanos , Pseudomonas syringae/genética , Café , Estudio de Asociación del Genoma Completo , Plásmidos/genética , Enfermedades de las Plantas/microbiología
4.
Sci Rep ; 13(1): 15151, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37704663

RESUMEN

Caffeine and trigonelline are found in Coffea arabica, and show antioxidant roles and growth and development functions. However, there are no reports on trigonelline and caffeine in relation to coffee rooting. The aim was to evaluate the impact of application of indole-3-butyric acid (IBA) and melatonin on caffeine and trigonelline at different stages of adventitious rooting in cuttings. In addition, to study the correlation between these metabolites and H2O2, phenols, and antioxidant enzymes. Four treatments (Control, melatonin 21 µM (M21), melatonin 43 µM (M43), and IBA 7380 µM (IBA)) were used, with four replications. The growth and biochemical parameters of the antioxidant system were performed in induction, initiation, and extension rooting stages. Higher concentrations of trigonelline and caffeine quantified in the induction and initiation stages were positively correlated with higher percentage of rooted cuttings. Trigonelline and caffeine were positively correlated with H2O2 in all stages of development of adventitious roots. The correlations of trigoneline and caffeine with phenols and antioxidant enzymes reveal different profiles, depending on the phases. The results indicate that IBA and melatonin increase trigonelline and caffeine during the induction and initiation of adventitious roots in Coffea arabica cuttings, which is correlated with a higher percentage of rooted cuttings.


Asunto(s)
Coffea , Melatonina , Cafeína , Antioxidantes , Peróxido de Hidrógeno , Fenoles
5.
Int J Mol Sci ; 24(15)2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37569839

RESUMEN

The use of transcriptomic data to make inferences about plant metabolomes is a useful tool to help the discovery of important compounds in the available biodiversity. To unveil previously undiscovered metabolites of Coffea, of phytotherapeutic and economic value, we employed 24 RNAseq libraries. These libraries were sequenced from leaves exposed to a diverse range of environmental conditions. Subsequently, the data were meticulously processed to create models of putative metabolic networks, which shed light on the production of potential natural compounds of significant interest. Then, we selected one of the predicted compounds, the L-3,4-dihydroxyphenylalanine (L-DOPA), to be analyzed by LC-MS/MS using three biological replicates of flowers, leaves, and fruits from Coffea arabica and Coffea canephora. We were able to identify metabolic pathways responsible for producing several compounds of economic importance. One of the identified pathways involved in isoquinoline alkaloid biosynthesis was found to be active and producing L-DOPA, which is a common product of POLYPHENOL OXIDASES (PPOs, EC 1.14.18.1 and EC 1.10.3.1). We show that coffee plants are a natural source of L-DOPA, a widely used medicine for treatment of the human neurodegenerative condition called Parkinson's disease. In addition, dozens of other compounds with medicinal significance were predicted as potential natural coffee products. By further refining analytical chemistry techniques, it will be possible to enhance the characterization of coffee metabolites, enabling a deeper understanding of their properties and potential applications in medicine.

6.
Mol Biotechnol ; 65(11): 1777-1795, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36790658

RESUMEN

Phosphites have been used as inducers of resistance, activating the defense of plants and increasing its ability to respond to the invasion of the pathogen. However, the mode of action of phosphites in defense responses has not yet been fully elucidated. The objective of this study was to evaluate the effect of potassium phosphite (KPhi) in coffee cultivars with different levels of resistance to rust to clarify the mechanism by which KPhi activates the constitutive defense of plants. To this end, we studied the expression of genes and the activity of enzymes involved in the defense pathway of salicylic acid (SA) and reactive oxygen species (ROS), in addition to the levels of total soluble phenolic compounds and soluble lignin. Treatment with KPhi induced constitutive defense responses in cultivars resistant and susceptible to rust. The results suggest that KPhi acts in two parallel defense pathways, SA and ROS, which are essential for the induction of systemic acquired resistance (SAR) when activated simultaneously. The activation of the mechanisms associated with defense routes demonstrates that KPhi is a potential inducer of resistance in coffee plants.


Asunto(s)
Coffea , Fosfitos , Especies Reactivas de Oxígeno/metabolismo , Fosfitos/metabolismo , Coffea/genética , Coffea/metabolismo , Café , Plantas/metabolismo , Enfermedades de las Plantas/genética , Ácido Salicílico/metabolismo , Regulación de la Expresión Génica de las Plantas
7.
Biosci. j. (Online) ; 39: e39055, 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1555749

RESUMEN

Rust is the main disease affecting Coffea arabica, the most economically important coffee species. The objective of this study was to analyze C. arabicacultivars with different levels of rust resistance, including bean size, raw bean appearance, finalsensory scores (FSS), and aromaand taste nuances of the coffee cup. The experiment was designed in randomized blocks (RBD) with three replications and 20 treatments (cultivars), totaling 60 experimental plots. The rust-susceptible cultivars IPR 100, Rubi MG 1192, and Topázio MG 1190 were compared with 17 rust-resistant cultivars.Cultivars IPR 103, MGS Aranãs, and SaíraII presented the highest percentages of high sieves, highest scores of raw bean appearance, and low percentages of mocha-type beans. All cultivars had FSS above 82 and were classified as specialty coffees. The cultivars with the highest FSS (Arara and Catiguá MG2) showed a greater diversity of coffee cup aroma and flavor nuances. Rust-resistant Arabica coffee cultivars are promising for the physical quality of beans and have potential for the specialty coffee market.

8.
Front Plant Sci ; 13: 989847, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36330243

RESUMEN

Bacteria halo blight (BHB), a coffee plant disease caused by Pseudomonas syringae pv. garcae, has been gaining importance in producing mountain regions and mild temperatures areas as well as in coffee nurseries. Most Coffea arabica cultivars are susceptible to this disease. In contrast, a great source of genetic diversity and resistance to BHB are found in C. arabica Ethiopian accessions. Aiming to identify quantitative trait nucleotides (QTNs) associated with resistance to BHB and the influence of these genomic regions during the domestication of C. arabica, we conducted an analysis of population structure and a Genome-Wide Association Study (GWAS). For this, we used genotyping by sequencing (GBS) and phenotyping for resistance to BHB of a panel with 120 C. arabica Ethiopian accessions from a historical FAO collection, 11 C. arabica cultivars, and the BA-10 genotype. Population structure analysis based on single-nucleotide polymorphisms (SNPs) markers showed that the 132 accessions are divided into 3 clusters: most wild Ethiopian accessions, domesticated Ethiopian accessions, and cultivars. GWAS, using the single-locus model MLM and the multi-locus models mrMLM, FASTmrMLM, FASTmrEMMA, and ISIS EM-BLASSO, identified 11 QTNs associated with resistance to BHB. Among these QTNs, the four with the highest values of association for resistance to BHB are linked to g000 (Chr_0_434_435) and g010741 genes, which are predicted to encode a serine/threonine-kinase protein and a nucleotide binding site leucine-rich repeat (NBS-LRR), respectively. These genes displayed a similar transcriptional downregulation profile in a C. arabica susceptible cultivar and in a C. arabica cultivar with quantitative resistance, when infected with P. syringae pv. garcae. However, peaks of upregulation were observed in a C. arabica cultivar with qualitative resistance, for both genes. Our results provide SNPs that have potential for application in Marker Assisted Selection (MAS) and expand our understanding about the complex genetic control of the resistance to BHB in C. arabica. In addition, the findings contribute to increasing understanding of the C. arabica domestication history.

9.
Front Plant Sci ; 13: 868581, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874027

RESUMEN

The largest family of disease resistance genes in plants are nucleotide-binding site leucine-rich repeat genes (NLRs). The products of these genes are responsible for recognizing avirulence proteins (Avr) of phytopathogens and triggering specific defense responses. Identifying NLRs in plant genomes with standard gene annotation software is challenging due to their multidomain nature, sequence diversity, and clustered genomic distribution. We present the results of a genome-wide scan and comparative analysis of NLR loci in three coffee species (Coffea canephora, Coffea eugenioides and their interspecific hybrid Coffea arabica). A total of 1311 non-redundant NLR loci were identified in C. arabica, 927 in C. canephora, and 1079 in C. eugenioides, of which 809, 562, and 695 are complete loci, respectively. The NLR-Annotator tool used in this study showed extremely high sensitivities and specificities (over 99%) and increased the detection of putative NLRs in the reference coffee genomes. The NLRs loci in coffee are distributed among all chromosomes and are organized mostly in clusters. The C. arabica genome presented a smaller number of NLR loci when compared to the sum of the parental genomes (C. canephora, and C. eugenioides). There are orthologous NLRs (orthogroups) shared between coffee, tomato, potato, and reference NLRs and those that are shared only among coffee species, which provides clues about the functionality and evolutionary history of these orthogroups. Phylogenetic analysis demonstrated orthologous NLRs shared between C. arabica and the parental genomes and those that were possibly lost. The NLR family members in coffee are subdivided into two main groups: TIR-NLR (TNL) and non-TNL. The non-TNLs seem to represent a repertoire of resistance genes that are important in coffee. These results will support functional studies and contribute to a more precise use of these genes for breeding disease-resistant coffee cultivars.

10.
PLoS One ; 17(2): e0258838, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35143519

RESUMEN

Pathogen-associated molecular patterns (PAMPs) are recognized by pattern recognition receptors (PRRs) localized on the host plasma membrane. These receptors activate a broad-spectrum and durable defense, which are desired characteristics for disease resistance in plant breeding programs. In this study, candidate sequences for PRRs with lysin motifs (LysM) were investigated in the Coffea arabica genome. For this, approaches based on the principle of sequence similarity, conservation of motifs and domains, phylogenetic analysis, and modulation of gene expression in response to Hemileia vastatrix were used. The candidate sequences for PRRs in C. arabica (Ca1-LYP, Ca2-LYP, Ca1-CERK1, Ca2-CERK1, Ca-LYK4, Ca1-LYK5 and Ca2-LYK5) showed high similarity with the reference PRRs used: Os-CEBiP, At-CERK1, At-LYK4 and At-LYK5. Moreover, the ectodomains of these sequences showed high identity or similarity with the reference sequences, indicating structural and functional conservation. The studied sequences are also phylogenetically related to the reference PRRs described in Arabidopsis, rice, and other plant species. All candidates for receptors had their expression induced after the inoculation with H. vastatrix, since the first time of sampling at 6 hours post-inoculation (hpi). At 24 hpi, there was a significant increase in expression, for most of the receptors evaluated, and at 48 hpi, a suppression. The results showed that the candidate sequences for PRRs in the C. arabica genome display high homology with fungal PRRs already described in the literature. Besides, they respond to pathogen inoculation and seem to be involved in the perception or signaling of fungal chitin, acting as receptors or co-receptors of this molecule. These findings represent an advance in the understanding of the basal immunity of this species.


Asunto(s)
Basidiomycota/genética , Coffea/genética , Proteínas de Plantas/genética , Receptores de Reconocimiento de Patrones/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Basidiomycota/fisiología , Coffea/metabolismo , Coffea/microbiología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expresión Génica , Genoma de Planta , Oryza/genética , Filogenia , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/clasificación , Proteínas de Plantas/metabolismo , Receptores de Reconocimiento de Patrones/clasificación , Receptores de Reconocimiento de Patrones/metabolismo , Alineación de Secuencia
11.
Food Chem ; 377: 131960, 2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-34979400

RESUMEN

This study evaluated green coffee seed residue (GCSR) as an alternative substrate for producing distilled beverages. Two proportions of GCSR, 10% and 20% (w/v), were fermented and distilled in a copper alembic still. The spirits were characterized by GC-FID, HS-SPME GC-MS, and sensory analysis by trained panelists. Most of the 62 identified volatile compounds were affected by the GCSR concentration. Total terpenes, higher alcohols, and acetals showed the highest concentrations in the 10% GCSR spirit. Esters, acetates, and aldehydes were most abundant in the 20% GCSR. In the sensory analysis, the 10% GCSR spirit was characterized by floral, dairy, and almond aromas, while the 20% GCSR spirit was embodied coffee, vegetable, hazelnut, cooked cabbage, and nut descriptors. The results demonstrate the potential of GCSR as a substrate for producing coffee spirits with chemical and sensory qualities, with the 10% GCSR being the better option for fermentation.


Asunto(s)
Café , Compuestos Orgánicos Volátiles , Bebidas/análisis , Fermentación , Cromatografía de Gases y Espectrometría de Masas , Odorantes/análisis , Compuestos Orgánicos Volátiles/análisis
12.
PLoS One ; 17(1): e0258822, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35100284

RESUMEN

Several researchers have attempted to develop coffee plants that are resistant to brown eye spot (BES); however, no coffee cultivars are resistant to the disease. In the present study, a blend of strains from Cercospora coffeicola was inoculated into 19 Brazilian commercial cultivars and 41 accessions from the Germplasm Collection of Minas Gerais to evaluate the genetic resistance ability within the population and select superior genotypes for the breeding program. After predicting the genotypic values of the estudied material, the evaluations number necessary for selecting genotypes with accuracy and efficiency was determined based on the data of severity to BES. The action of defense mechanisms plant was also investigated by assessing the levels of total soluble phenolic compounds and soluble lignin in contrasting genotypes for disease susceptibility. Based on the results, the accession MG 1207 Sumatra, had an intrinsic genetic capacity to maintain low levels of severity to BES. The genotype MG 1207 Sumatra can substantially contribute to the development of new cultivars, which may lead to the reduced use of pesticides. According to the accuracy and efficiency results obtained, four evaluations BES severity are sufficient to achieve accuracy, providing expressive genetic gains. Finally, the levels of lignin and phenolic compounds were not found to be associated with the resistance of coffee genotypes to BES.


Asunto(s)
Coffea/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Brasil , Coffea/química , Coffea/metabolismo , Genotipo , Lignina/metabolismo , Fenoles/análisis
13.
Mol Biotechnol ; 64(3): 263-277, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34595725

RESUMEN

Coffea arabica is the most economically important coffee species worldwide. However, its production is severely limited by diseases such as rust. The mechanisms underlying constitutive defense responses in coffee are still poorly understood, compared with induced defense mechanisms. We aimed to characterize constitutive defense responses of thirteen cultivars of C. arabica. Cultivars were classified under field conditions according to the level of resistance to rust: resistant (R), moderately resistant (MR), and susceptible (S). Based on this classification, the stability of eight reference genes (RGs) was evaluated. The most stable RGs were EF1α, APT1, and 24S. We also evaluated the expression of CaWRKY1, CaPAL1, CaCAD1, and CaPOX1, and activities of PAL, CAD, and POX, which are involved in lignin biosynthesis, and leaf content of total phenolic compounds and lignin. Gene expression and enzymatic activity were not correlated with defense metabolites in the R cultivar group but showed a negative correlation with phenolic compounds in MR cultivars. Cultivar S showed positive correlations of gene expression and enzyme activity with phenolic compounds. These results may assist coffee breeding programs regarding selection of genotypes and in optimization of rust resistance.


Asunto(s)
Café/crecimiento & desarrollo , Resistencia a la Enfermedad , Proteínas de Plantas/genética , Café/clasificación , Café/genética , Café/microbiología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Lignina/biosíntesis , Fenoles/metabolismo , Hojas de la Planta/clasificación , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/microbiología
14.
Plants (Basel) ; 10(9)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34579447

RESUMEN

Coffee production is one of the main agricultural activities in Brazil, and several coffee cultivars with disease resistance have already been developed. The secondary metabolites produced by plants are closely associated with defense strategies, and the resistance of coffee cultivars to bacterial halo blight (BHB) can be related to these compounds. Therefore, this study aims to compare a partially resistant coffee cultivar (Iapar-59) and a susceptible cultivar (Mundo Novo 376/4) to BHB (Pseudomonas syringae pv. garcae) in relation to the chemical composition and antioxidant activity of the leaf extracts. In addition, this study determined the total phenolic and flavonoid contents and phenolic profiles of the Iapar-59 leaf extracts of plants inoculated with P. syringae pv. garcae. The Iapar-59 extract showed a higher content of phenolic compounds and flavonoids than the Mundo Novo 376/4 extract. Both cultivars contained gallic, chlorogenic and caffeic acids; however, the highest contents were quantified in the Iapar-59 cultivar. The leaf extracts from the Iapar-59 cultivar exhibited higher antioxidant activity. Higher concentrations of gallic, caffeic and chlorogenic acids and the presence of vanillin were detected in the extract of cultivar Iapar-59 inoculated with P. syringae pv. garcae.

15.
Br J Neurosurg ; : 1-4, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34148487

RESUMEN

PURPOSE: We describe a rare case of histopathologic-proven necrotizing infundibulo-hypophysitis (NIH). CLINICAL HISTORY: A 40-year-old female presented with coexistence of central diabetes insipidus and hypopituitarism. Imaging disclosed a thickened infundibulum and a diffusely enlarged pituitary mass with gadolinium rim enhancement pattern. Microsurgical endonasal transsphenoidal resection was performed. The presence of extensive liquefactive necrosis, surrounded by lymphoplasmocytic inflammatory infiltrate, allowed for the diagnosis of NIH. Follow-up cranial imaging 10 months after surgery showed no evidence of reappearance of the lesion. There was no progression to panhypopituitarism. CONCLUSION: Surgery and histopathological confirmation are the key diagnostic feature in NIH. The current case is the fifth report of NIH and the first one with an indolent course and without progression to panhypopituitarism so far.

16.
Br J Neurosurg ; 35(3): 364-366, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29607688

RESUMEN

Carcinoid tumors are generally indolent neoplasms. Brain metastases are rare and when present, yield a poor prognosis. We present the case of a 76-year old female surgically treated for an atypical bronchial carcinoid, staged as T2aN0M0G2. Without further adjuvant treatment she remained stable for four years, when she presented with headaches and gait imbalance. Brain MRI revealed a midline, intra-axial infratentorial lesion that was completely removal, of which histolology confirmed a carcinoid metastasis. At 14 months of follow-up, the patient showed no signs of systemic disease or brain recurrence, and thus no adjuvant radiotherapy was prescribed.


Asunto(s)
Tumor Carcinoide , Neoplasias Pulmonares , Anciano , Tumor Carcinoide/diagnóstico por imagen , Tumor Carcinoide/cirugía , Femenino , Humanos , Pulmón , Neoplasias Pulmonares/diagnóstico por imagen , Recurrencia Local de Neoplasia , Radioterapia Adyuvante
17.
J Food Sci Technol ; 57(12): 4481-4491, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33087961

RESUMEN

Coffee is one of the most important commodities worldwide. The industrial processing of coffee cherries generates a considerable volume of by-products such as wastewater, coffee pulp, mucilage, and husk. These by-products have sugars and nutrients that can be converted into value-added products via microbial action. In this study, for the first time, we evaluated the potential of coffee pulp and coffee wastewater as substrate for alcoholic fermentation produce a distilled beverage. The must composed by dry or wet coffee pulp and coffee wastewater added of commercial sucrose or sugarcane molasses was fermented by S. cerevisiae. After a screening step, a larger fermentation was carried out with the wet pulp added of sucrose due to its higher alcoholic fermentation efficiency. The distilled beverage contained 38% (v/v) ethanol and 0.2 g/L of acetic acid. The contaminants furfural, hydroxymethylfurfural and ethyl carbamate were below detection level. Among the 48 volatile compounds detected, the majority (21) were ethyl esters usually associated with floral and sweet aromas. Ethyl decanoate (996.88 µg/L) and ethyl dodecanoate (1088.09 µg/L) were the most abundant esters. Coffee spirit presented taste acceptance of 80% and sugarcane spirit, 70%. The tasters indicated an aroma acceptance of 86% for the coffee spirit and 78% for the sugarcane spirit. The results of this work demonstrate the potential for using coffee by-products to produce a good quality distilled beverage. Considering our results, especially sensorial analysis, we can infer that the produced coffee beverage represents a new alternative for adding value to the coffee production chain.

18.
Front Plant Sci ; 11: 309, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32265962

RESUMEN

Epidemics of coffee leaf rust (CLR) leads to great yield losses and huge depreciation of coffee marketing values, if no control measures are applied. Societal expectations of a more sustainable coffee production are increasingly imposing the replacement of fungicide treatments by alternative solutions. A protection strategy is to take advantage of the plant immune system by eliciting constitutive defenses. Based on such concept, plant resistance inducers (PRIs) have been developed. The Greenforce CuCa formulation, similarly to acibenzolar-S-methyl (ASM), shows promising results in the control of CLR (Hemileia vastatrix) in Coffea arabica cv. Mundo Novo. The molecular mechanisms of PRIs action are poorly understood. In order to contribute to its elucidation a proteomic, physiological (leaf gas-exchange) and biochemical (enzymatic) analyses were performed. Coffee leaves treated with Greenforce CuCa and ASM and inoculation with H. vastatrix were considered. Proteomics revealed that both PRIs lead to metabolic adjustments but, inducing distinct proteins. These proteins were related with photosynthesis, protein metabolism and stress responses. Greenforce CuCa increased photosynthesis and stomatal conductance, while ASM caused a decrease in these parameters. It was further observed that Greenforce CuCa reinforces the redox homeostasis of the leaf, while ASM seems to affect preferentially the secondary metabolism and the stress-related proteins. So, the PRIs prepare the plant to resist CLR but, inducing different defense mechanisms upon pathogen infection. The existence of a link between the primary metabolism and defense responses was evidenced. The identification of components of the plant primary metabolism, essential for plant growth and development that, simultaneously, participate in the plant defense responses can open new perspectives for plant breeding programs.

19.
PLoS One ; 14(4): e0215598, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30998802

RESUMEN

Coffee leaf rust caused by the fungus Hemileia vastatrix is one of the most important leaf diseases of coffee plantations worldwide. Current knowledge of the H. vastatrix genome is limited and only a small fraction of the total fungal secretome has been identified. In order to obtain a more comprehensive understanding of its secretome, we aimed to sequence and assemble the entire H. vastatrix genome using two next-generation sequencing platforms and a hybrid assembly strategy. This resulted in a 547 Mb genome of H. vastatrix race XXXIII (Hv33), with 13,364 predicted genes that encode 13,034 putative proteins with transcriptomic support. Based on this proteome, 615 proteins contain putative secretion peptides, and lack transmembrane domains. From this putative secretome, 111 proteins were identified as candidate effectors (EHv33) unique to H. vastatrix, and a subset consisting of 17 EHv33 genes was selected for a temporal gene expression analysis during infection. Five genes were significantly induced early during an incompatible interaction, indicating their potential role as pre-haustorial effectors possibly recognized by the resistant coffee genotype. Another nine genes were significantly induced after haustorium formation in the compatible interaction. Overall, we suggest that this fungus is able to selectively mount its survival strategy with effectors that depend on the host genotype involved in the infection process.


Asunto(s)
Basidiomycota/fisiología , Coffea/microbiología , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , Genoma Fúngico , Interacciones Huésped-Patógeno , Enfermedades de las Plantas/microbiología , Secuenciación Completa del Genoma
20.
Ciênc. rural ; 46(10): 1764-1770, Oct. 2016. graf
Artículo en Inglés | LILACS | ID: lil-792531

RESUMEN

ABSTRACT: Brown eye spot (BE) caused by Cercospora coffeicola is the main disease of coffee crop. A variation in symptoms of BE has been reported in the field, raising suspicion of occurrence of new species. However, information about coffee- C. coffeicola interaction is still limited. This research aimed to determine the difference between antioxidant metabolism of coffee plants cultivar Mundo Novo inoculated with a strain isolated from a common BE lesion (CML 2984) and a strain isolated from a black BE lesion (CML 2985). The enzyme activity of peroxidase (POX), catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) were determined. Activities of POX, APX, and PAL increased in plants inoculated with both strains compared to non-inoculated plants at 12 and 24 hours post inoculation (hpi). CAT activity increased in inoculated plants with black BE strain at 24 hpi and both strains at 48 hpi. The SOD activity only increased in inoculated plants with both strains at 48 hpi. These results show that an elevated antioxidant response was observed when the plants were challenged with both strains of C. coffeicola. Both strains produced lesions of the common type, suggesting that other factors lead to the development of black BE lesion type under field conditions and further investigation is needed.


RESUMO: A cercosporiose, causada pelo fungo Cercospora coffeicola, é uma das principais doenças que afeta o cafeeiro. Uma variação nos sintomas de cercosporiose foi encontrada no campo, levantando suspeitas da ocorrência de uma nova espécie. Considerando que informações sobre a interação cafeeiro-C. coffeicola ainda são limitadas, objetivou-se, neste trabalho, determinar diferenças no metabolismo oxidativo de plantas de cafeeiro, cultivar 'Mundo Novo', inoculadas com isolado proveniente de lesões de cercosporiose do tipo olho pardo (CML 2984) e isolado proveniente de lesões de cercosporiose do tipo negra (CML 2985). Foram determinadas a atividade das enzimas peroxidase (POX), catalase (CAT), superóxido dismutase (SOD), ascorbato peroxidase (APX) e fenilalanina amônia liase (PAL). As atividades das enzimas POX, APX e PAL aumentaram nas plantas inoculadas com ambos os isolados, quando comparadas com as plantas não inoculadas às 12 e 24 horas após inoculação (hai). A atividade da CAT aumentou nas plantas inoculadas com o isolado que causa sintomas de cercosporiose do tipo negra às 24 hai e, para ambos os isolados, às 48 hai. Plantas inoculadas com ambos os isolados demonstraram aumento na atividade da SOD somente às 48 hai. Este estudo mostrou que uma resposta antioxidante elevada foi observada quando as plantas foram inoculadas com os dois isolados de C. coffeicola . Ambos os isolados produziram lesões de cercosporiose do tipo comum, sugerindo que outros fatores que causam lesões de cercosporiose do tipo negra ainda necessitam ser investigados.

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