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1.
Plant Physiol Biochem ; 212: 108753, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38781637

RESUMEN

Biocompounds are metabolites synthesized by plants, with clinically proven capacity in preventing and treating degenerative diseases in humans. Carbon-based nanomaterials (CNMs) are atomic structures that assume different hybridization and shape. Due to the reactive property, CNMs can induce the synthesis of metabolites, such as biocompounds in cells and various plant species, by generating reactive oxygen species (ROS). In response, plants positively or negatively regulate the expression of various families of genes and enzymes involved in physiological and metabolomic pathways of plants, such as carbon and nitrogen metabolism, which are directly involved in plant development and growth. Likewise, ROS can modulate the expression of enzymes and genes related to the adaptation of plants to stress, such as the glutathione ascorbate cycle, the shikimic acid, and phenylpropanoid pathways, from which the largest amount of biocompounds in plants are derived. This document exposes the ability of three CNMs (fullerene, graphene, and carbon nanotubes) to positively or negatively regulate the activity of enzymes and genes involved in various plant species' primary and secondary metabolism. The mechanism of action of CNMs on the production of biocompounds and the effect of the translocation of CNMs on the growth and content of primary metabolites in plants are described. Adverse effects of CNMs on plants, prospects, and possible risks involved are also discussed. The use of CNMs as inducers of biocompounds in plants could have implications and relevance for human health, crop quality, and plant adaptation and resistance to biotic and abiotic stress.


Asunto(s)
Nanoestructuras , Plantas , Nanoestructuras/química , Plantas/metabolismo , Plantas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Carbono/metabolismo , Nanotubos de Carbono , Fulerenos/farmacología , Fulerenos/metabolismo , Grafito
3.
Sci Rep ; 13(1): 19888, 2023 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-37964003

RESUMEN

Fructans found in agave are called agavins, highly branched neo-fructans. They are essential on the yield and quality of Tequila production. The need for agave specimens with higher accumulation of agavins became essential before the growing demand of such products. To get such specimens, understanding agavins metabolism is a quintessential requirement. For this, a more efficient biological model is required. The recently reclassified Agave amica possesses the potential to gather the requirements for becoming such a model. Therefore, this study dealt with the characterization of carbohydrates in the bulbs of A. amica focusing on fructans. Moreover, it tested and described its feasibility as model for the accelerated study of agavins. Infrared analysis unveiled potential content of fructans in the bulbs of A. amica. Furthermore, high performance thin layer chromatography detected fructooligosaccharides. High performance anion exchange chromatography confirmed a polydisperse mixture of branched fructans. Gas chromatography-mass spectrometry analysis demonstrated agavins like structures in the bulbs of A. amica. Moreover, total fructan content and multivariate data analysis through bulb's age demonstrated their correlation. Thus, the presence of agavins, their correlation with phenology, and their technical advantages highlighted the feasibility of this species as a potential new biological model for the study of agavins' metabolism.


Asunto(s)
Agave , Agave/metabolismo , Carbohidratos , Cromatografía en Capa Delgada , Fructanos/metabolismo
4.
Curr Res Food Sci ; 6: 100451, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36798949

RESUMEN

Fructans are categorized as fructose-based metabolites with no more than one glucose in their structure. Agave species possess a mixture of linear and ramified fructans with different degrees of polymerization. Among them, fructooligosaccharides are fructans with low degree of polymerization which might be approachable by high performance thin layer chromatography (HPTLC). Thus, this study used two emblematic Agave species collected at different ages as models to explore the feasibility of HPTLC-based fingerprinting to characterize fructooligosaccharides (FOS) production, accumulation, and behavior through time. To do so, high performance anion exchange was also used as analytical reference to determine the goodness and robustness of HPTLC data. The multivariate data analysis showed separation of samples dictated by species and age effects detected by both techniques. Moreover, linear correlations between the increase of the age in agave and their carbohydrate fraction was established in both species by both techniques. Oligosaccharides found to be correlated to species and age factors, these suggest changes in specific carbohydrate metabolism enzymes. Thus, HPTLC was proven as a complementary or stand-alone fingerprinting platform for fructooligosaccharides characterization in biological mixtures. However, the type of derivatizing reagent and the extraction color channel determined the goodness of the model used to scrutinize agavin fructooligosaccharides (aFOS).

5.
Food Chem ; 415: 135767, 2023 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-36842374

RESUMEN

Agavins (fructans from the agave plant) are used for their technological and prebiotic properties in developing functional foods. In this study, four extraction methods were evaluated: ultrasound (U), microwave (M), simultaneous ultrasound-microwave (UM), and heat treatment (HT). Isomers with a degree of polymerization (DP) > 10, as well as a significant concentration of fructooligosaccharides (FOS) were identified. The yield obtained by UM (72%) was similar to the other methods; however, the extraction time was shorter (5 min). In U, M, and HT the yields were 86, 76, and 85% in 35, 30, and 180 min, respectively. In addition, FTIR spectra showed evidence of regions corresponding to fatty acids and carbohydrates. Therefore, using UM to obtain agavins is a more ecological and faster process.


Asunto(s)
Agave , Calor , Fructanos , Microondas , Carbohidratos
6.
ACS Omega ; 7(35): 30756-30767, 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36092630

RESUMEN

The COVID-19 pandemic has caused major disturbances to human health and economy on a global scale. Although vaccination campaigns and important advances in treatments have been developed, an early diagnosis is still crucial. While PCR is the golden standard for diagnosing SARS-CoV-2 infection, rapid and low-cost techniques such as ATR-FTIR followed by multivariate analyses, where dimensions are reduced for obtaining valuable information from highly complex data sets, have been investigated. Most dimensionality reduction techniques attempt to discriminate and create new combinations of attributes prior to the classification stage; thus, the user needs to optimize a wealth of parameters before reaching reliable and valid outcomes. In this work, we developed a method for evaluating SARS-CoV-2 infection and COVID-19 disease severity on infrared spectra of sera, based on a rather simple feature selection technique (correlation-based feature subset selection). Dengue infection was also evaluated for assessing whether selectivity toward a different virus was possible with the same algorithm, although independent models were built for both viruses. High sensitivity (94.55%) and high specificity (98.44%) were obtained for assessing SARS-CoV-2 infection with our model; for severe COVID-19 disease classification, sensitivity is 70.97% and specificity is 94.95%; for mild disease classification, sensitivity is 33.33% and specificity is 94.64%; and for dengue infection assessment, sensitivity is 84.27% and specificity is 94.64%.

7.
Plants (Basel) ; 11(14)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35890468

RESUMEN

Despite the recognition of Agave tequilana Weber var. Azul as raw material for producing tequila and obtaining prebiotics, there are other highly relevant Agave species in Mexico. Oaxaca contains a startlingly diverse range of Agave species; Agave angustifolia Haw. and Agave potatorum Zucc. are two classic specimens with great commercial potential. In this study, we examined the fructan fluctuation in these two species during their lifetime in the field (from 1 to 6 years old). First, we analyzed their morphological diversity based on vegetative characteristics. Subsequently, fructan extracts were analyzed by TLC, FT-IR, and HPAEC-PAD to identify carbohydrates. Multivariate analyses of the morphological parameters indicated a morphological divergence between the two species. Furthermore, we found that the concentration of simple carbohydrates and fructans, as well as the fructan DP, changed during plant development. Glucose, fructose, and fructooligosaccharides (FOS) were more abundant in A. potatorum, while A. angustifolia showed a greater amount of sucrose and fructans with a high DP. Fructan DP heatmaps were constructed using HPAEC-PAD profiles-the heatmaps were very helpful for establishing an easy correlation between age and the carbohydrate types present in the fructan extracts. This study is an important contribution to the agave fructan knowledge of the Mexican agave diversity.

8.
Plants (Basel) ; 11(11)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35684270

RESUMEN

Resilience of growing in arid and semiarid regions and a high capacity of accumulating sugar-rich biomass with low lignin percentages have placed Agave species as an emerging bioenergy crop. Although transcriptome sequencing of fiber-producing agave species has been explored, molecular bases that control wall cell biogenesis and metabolism in agave species are still poorly understood. Here, through RNAseq data mining, we reconstructed the cellulose biosynthesis pathway and the phenylpropanoid route producing lignin monomers in A. tequilana, and evaluated their expression patterns in silico and experimentally. Most of the orthologs retrieved showed differential expression levels when they were analyzed in different tissues with contrasting cellulose and lignin accumulation. Phylogenetic and structural motif analyses of putative CESA and CAD proteins allowed to identify those potentially involved with secondary cell wall formation. RT-qPCR assays revealed enhanced expression levels of AtqCAD5 and AtqCESA7 in parenchyma cells associated with extraxylary fibers, suggesting a mechanism of formation of sclerenchyma fibers in Agave similar to that reported for xylem cells in model eudicots. Overall, our results provide a framework for understanding molecular bases underlying cell wall biogenesis in Agave species studying mechanisms involving in leaf fiber development in monocots.

9.
Foods ; 11(5)2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35267303

RESUMEN

Agavins are prebiotics and functional fiber that modulated the gut microbiota and metabolic status in obese mice. Here, we designed a placebo-controlled, double-blind, exploratory study to assess fluctuations in gastrointestinal (GI) tolerability-related symptoms to increasing doses of agavins in 38 lean and obese Mexican adults for five weeks and their impact on subjective appetite, satiety, metabolic markers, and body composition. All GI symptoms showed higher scores than placebo at almost every dose for both lean and obese groups. Flatulence caused an intense discomfort in the lean-agavins group at 7 g/day, while obese-agavins reported a mild-to-moderate effect for all five symptoms: no significant differences among 7, 10, and 12 g/day for flatulence, bloating, and diarrhea. Ratings for any GI symptom differed between 10 and 12 g/day in neither group. The inter-group comparison demonstrated a steady trend in GI symptoms scores in obese participants not seen for lean volunteers that could improve their adherence to larger trials. Only body weight after 10 g/day reduced from baseline conditions in obese-agavins, with changes in triglycerides and very-low-density lipoproteins compared to placebo at 5 g/day, and in total cholesterol for 10 g/day. Altogether, these results would help design future trials to evaluate agavins impact on obese adults.

10.
Biomolecules ; 11(10)2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34680096

RESUMEN

Botryococcus braunii produce liquid hydrocarbons able to be processed into combustion engine fuels. Depending on the growing conditions, the cell doubling time can be up to 6 days or more, which is a slow growth rate in comparison with other microalgae. Few studies have analyzed the cell cycle of B. braunii. We did a bioinformatic comparison between the protein sequences for retinoblastoma and cyclin-dependent kinases from the A (Yamanaka) and B (Showa) races, with those sequences from other algae and Arabidopsis thaliana. Differences in the number of cyclin-dependent kinases and potential retinoblastoma phosphorylation sites between the A and B races were found. Some cyclin-dependent kinases from both races seemed to be phylogenetically more similar to A. thaliana than to other microalgae. Microscopic observations were done using several staining procedures. Race A colonies, but not race B, showed some multinucleated cells without chlorophyll. An active mitochondrial net was detected in those multinucleated cells, as well as being defined in polyphosphate bodies. These observations suggest differences in the cell division processes between the A and B races of B. braunii.


Asunto(s)
Secuencia de Aminoácidos/genética , División Celular/genética , Hidrocarburos/metabolismo , Microalgas/genética , Arabidopsis/genética , Ciclo Celular/genética , Linaje de la Célula/genética , Clorofila/genética , Simulación por Computador , Hidrocarburos/química , Microalgas/crecimiento & desarrollo , Fotosíntesis/genética
11.
PLoS One ; 16(8): e0256016, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34383828

RESUMEN

Mitochondria participate in multiple functions in eukaryotic cells. Although disruption of mitochondrial function has been associated with energetic deregulation in cancer, the chronological changes in mitochondria during cancer development remain unclear. With the aim to assess the role of mitochondria throughout cancer development, we analyzed samples chronologically obtained from induced hepatocellular carcinoma (HCC) in rats. In our analyses, we integrated mitochondrial proteomic data, mitochondrial metabolomic data and nuclear genome transcriptomic data. We used pathway over-representation and weighted gene co-expression network analysis (WGCNA) to integrate expression profiles of genes, miRNAs, proteins and metabolite levels throughout HCC development. Our results show that mitochondria are dynamic organelles presenting specific modifications in different stages of HCC development. We also found that mitochondrial proteomic profiles from tissues adjacent to nodules or tumor are determined more by the stage of HCC development than by tissue type, and we evaluated two models to predict HCC stage of the samples using proteomic profiles. Finally, we propose an omics integration pipeline to massively identify molecular features that could be further evaluated as key regulators, biomarkers or therapeutic targets. As an example, we show a group of miRNAs and transcription factors as candidates, responsible for mitochondrial metabolic modification in HCC.


Asunto(s)
Carcinoma Hepatocelular/patología , Dietilaminas/toxicidad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Metaboloma , Mitocondrias/metabolismo , Proteoma/metabolismo , Transcriptoma , Animales , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Mitocondrias/efectos de los fármacos , Proteoma/análisis , Ratas , Ratas Endogámicas F344
12.
Trop Anim Health Prod ; 53(1): 101, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33417070

RESUMEN

This study investigated Lippia palmeri Watt (oregano) phytochemical compounds, their antioxidant capacity, and immunological effects on goat peripheral blood leukocytes (PBL), and on the presence of intermediate polar compounds in goat feces fed dietary oregano. The polar and nonpolar fractions of L. palmeri W. were characterized and phytochemical contents and antioxidant capacity were determined. Twelve healthy Anglo-Nubian goats were used for the in vivo trials, which were randomly assigned to control fed with basal diet, or oregano group fed with basal diet + 2.6% (DM basis) dried oregano leaves. Goat peripheral blood leukocytes (PBL) were isolated for the in vitro study, and PBL were stimulated with oregano extracts at 100 and 150 µg/mL after 24 h. For the in vivo trial, dietary oregano (2.6% on DM basis) was evaluated in the goats for 90 days. Relatively high abundance of carvacrol and thymol phytochemical compounds was found in oregano. The highest antioxidant capacity of oregano extracts was detected at 100 and 150 µg/mL. Nitric oxide production, phagocytosis, and superoxide dismutase activities increased (p < 0.05) in stimulated PBL with oregano extracts, whereas the pro-inflammatory (TNF-α and IL-1ß) transcription and antioxidant (CAT and GPX-4) genes downregulated. In the in vivo experiment, dietary oregano enabled the detection of nine compounds found in goat feces, from which caproic (C6) was in a high relative quantity compared with the control group. Oregano has phytochemical compounds with strong antioxidant capacity that protect cells against oxidative stress damage and could modulate immune response and feces composition in goats.


Asunto(s)
Antioxidantes/farmacología , Cabras/fisiología , Intestinos/fisiología , Leucocitos/inmunología , Lippia/química , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Femenino , Extractos Vegetales/administración & dosificación , Distribución Aleatoria
13.
Foods ; 9(12)2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33287102

RESUMEN

Highly branched neo-fructans (agavins) are natural prebiotics found in Agave plants, with a large capacity to mitigate the development of obesity and metabolic syndrome. Here, we investigated the impact of agavins intake on gut microbiota modulation and their metabolites as well as their effect on metabolic endotoxemia and low-grade inflammation in mice fed high-fat diet. Mice were fed with a standard diet (ST) and high-fat diet (HF) alone or plus an agavins supplement (HF+A) for ten weeks. Gut microbiota composition, fecal metabolite profiles, lipopolysaccharides (LPS), pro-inflammatory cytokines, and systemic effects were analyzed. Agavins intake induced substantial changes in gut microbiota composition, enriching Bacteroides, Parabacteroides, Prevotella, Allobaculum, and Akkermansia genus (LDA > 3.0). l-leucine, l-valine, uracil, thymine, and some fatty acids were identified as possible biomarkers for this prebiotic supplement. As novel findings, agavins supplementation significantly decreased LPS and pro-inflammatory (IL-1α, IL-1ß, and TNF-α; p < 0.05) cytokines levels in portal vein. In addition, lipid droplets content in the liver and adipocytes size also decreased with agavins consumption. In conclusion, agavins supplementation mitigate metabolic endotoxemia and low-grade inflammation in association with gut microbiota regulation and their metabolic products, thus inducing beneficial responses on metabolic disorders in high-fat diet-fed mice.

14.
Plant Foods Hum Nutr ; 75(1): 96-102, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31853903

RESUMEN

Agave bagasse is a fibrous-like material obtained during aguamiel extraction, which is also in contact with indigenous microbiota of agave plant during aguamiel fermentation. This plant is a well-known carrier of the prebiotic fructan-type carbohydrates, which have multiple ascribable health benefits. In the present work, the potential of ashen and green agave bagasse as functional ingredients in supplemented cookies was studied. For its application, the chemical, functional, properties of agave bagasses and formulated cookies were evaluated, as well as the physical properties of cookies. Chemical characterization was carried out by the proximate analysis of both bagasses and cookies, besides, the analysis of oligosaccharides was made by thin-layer chromatography and high-performance anion-exchange chromatography. In the same way, functional properties such as oil holding capacity, organic molecule absorption capacity, swelling capacity, and water holding capacity were analyzed in both agave bagasses and supplemented cookies. Finally, modifications in color and texture due to bagasse addition was studied through an analysis of total color difference and a penetrometric test, respectively. In this sense, ashen and green agave bagasses demonstrated chemical and functional properties for use in the food industry, since they increased oil holding capacity of cookies and transferred prebiotic fructooligosaccharides to both agave bagasse formulations, which remain active as a prebiotic ingredient in cookies after in vitro digestion and cookie manufacture, including thermal treatment. Hence, agave bagasse could be considered a valuable alternative for the addition of the nutritionally-relevant dietary fiber in healthier foods.


Asunto(s)
Agave , Celulosa , Alimentos Fortificados , Fructanos , Prebióticos
15.
Foods ; 8(9)2019 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-31547254

RESUMEN

In this study, we characterize fructan extracts from five wild agave varieties at three ages to identify their potential use in the food industry. Physicochemical parameters (solids soluble total and pH), sugar content and fructan distribution profiles by high-performance anion-exchange chromatography (HPAEC) were evaluated. We found that the ages and variety influenced the carbohydrate content and also fructan dispersion. Two- to four-year-old plants exhibited the highest concentrations of free sugars and fructans, with a low apparent degree of polymerization (DPa) of ≤9 monomers, which highlights their potential use as prebiotics. Conversely, 10- to 12-year-old plants presented a low concentration of free sugars and fructans with a maximum DPa of 70 monomers, which can be used to obtain fractions with high, intermediate and low DPa. These fractions have a potential use in the food industry as prebiotic, soluble fibers, stabilizers and sweeteners, among others. The agave varieties Agave spp., Agave salmiana, and Agave atrovirens showed mainly fructooligosaccharides (FOSs). Due to the presence of these low molecular carbohydrates, prebiotics, fermented products and/or syrups could be obtained. A. salmiana spp. crassipina and Agave tequilana variety cenizo presented DPa ≤50 and DPa ≤70, respectively, which could be useful in the production of fructan fractions of different DPa. These fractions might be used as functional ingredients in the manufacture of a wide range of food products.

16.
Molecules ; 24(15)2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31374810

RESUMEN

Capsaicin is a chemical compound found in pungent chili peppers (Capsicum spp.). In biotechnology, capsaicin has been proposed as a pathogen control; however, its low solubility in water and high instability limits its uses. The aim of this work was to study the effect of high concentrations of capsaicin on the synthesis of nanoparticles and to evaluate their inhibitory effect on the growth of Rhodotorula mucilaginosa yeast. Bovine serum albumin (BSA)-capsaicin nanoparticles were formulated at 0, 16.2, 32.5, 48.7 and 65.0 µg of capsaicin per mg of BSA. Nanoparticle properties were evaluated and they were added to cultures of R. mucilaginosa to quantify their effect on cell viability. We found that increased capsaicin levels caused several changes to the physicochemical parameters, probably due to changes in the hydrophobicity sites of the albumin during the nanostructuration. The administration of nanoparticles to cultures of R. mucilaginosa produced a maximal viability with nanoparticles at 16.2 µg/mg; on the contrary, nanoparticles at 65.0 µg/mg caused maximal cell death. R. mucilaginosa cells displayed a hormesis effect in response to the nanoparticle dose concentration. The nanoparticles showed different responses during the uptake process, probably as a consequence of the nanostructural properties of capsaicin in the BSA molecules.


Asunto(s)
Capsaicina/química , Nanopartículas/química , Rhodotorula/efectos de los fármacos , Capsaicina/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Hormesis , Humanos , Rhodotorula/patogenicidad , Albúmina Sérica Bovina/química
17.
Appl Biochem Biotechnol ; 184(1): 25-34, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28584965

RESUMEN

Recently, agavins (branched neo-fructans) of short degree of polymerization have shown beneficial effects on the health of both healthy and overweight individuals. Therefore, the aim of the present work was to investigate the potential use of Agave angustifolia agavins on the generation of branched fructooligosacharides (a-FOS). A. angustifolia agavins were hydrolyzed using exo-, endo-inulinase, and a mixture of both (25 and 75%, respectively). Exo- and the inulinase mixture degraded quickly the agavins in relation to endo-inulinase treatment. Only endo-inulinase and the inulinase mixture generated a-FOS formation. Endo-inulinase degraded 31% of agavins, yielding approximately 20% of a-FOS after 48 h, whereas the inulinase mixture hydrolyzed 33% of agavins in just 90 min, but only yielded 10% of a-FOS. These results suggest that agave plants could be an abundant raw material for a-FOS production, which might have a huge prebiotic potential as new branched fructooligosaccharides with many applications in the alimentary and pharmaceutical industry.


Asunto(s)
Agave/metabolismo , Fructanos/metabolismo , Glicósido Hidrolasas/metabolismo , Resinas de Intercambio Aniónico , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Cromatografía en Capa Delgada , Fructosa/metabolismo , Glucosa/metabolismo , Hidrólisis
18.
Res Microbiol ; 168(8): 740-750, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28774774

RESUMEN

Saccharomyces cerevisiae is a model to understand basic aspects of protein glycosylation pathways. Although these metabolic routes have been thoroughly studied, there are still knowledge gaps; among them, the role of the MNT1/KRE2 gene family. This family is composed of nine members, with only six functionally characterized. The enzymes Ktr1, Ktr3, and Mnt1/Kre2 have overlapping activities in both O-linked and N-linked glycan synthesis; while Ktr2 and Yur1 participate exclusively in the elongation of the N-linked glycan outer chain. KTR6 encodes for a phosphomannosyltransferase that synthesizes the cell wall phosphomannan. Here, we aimed to establish the functional role of KTR4, KTR5 and KTR7 in the protein glycosylation pathways, by using heterologous complementation in Candida albicans null mutants lacking members of the MNT1/KRE2 gene family. The three S. cerevisiae genes restored defects in the C. albicans N-linked glycosylation pathway. KTR5 and KTR7 partially complemented a C. albicans null mutant with defects in the synthesis of O-linked glycans, and only KTR4 fully elongated the O-linked glycans like wild-type cells. Therefore, our results suggest that the three genes have a redundant activity in the S. cerevisiae N-linked glycosylation pathway, but KTR4 plays a major role in O-linked glycan synthesis.


Asunto(s)
Manosiltransferasas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Candida albicans/genética , Candida albicans/metabolismo , Glicosilación , Manosiltransferasas/química , Manosiltransferasas/genética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
19.
Front Microbiol ; 8: 843, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28539922

RESUMEN

Sporothrix schenckii sensu stricto and S. brasiliensis are usually associated to sporotrichosis, a subcutaneous mycosis worldwide distributed. Comparative analyses between these two species indicate they contain genetic and physiological differences that are likely to impact the interaction with host cells. Here, we study the composition of the cell wall from conidia, yeast-like cells and germlings of both species and found they contained the same sugar composition. The carbohydrate proportion in the S. schenckii sensu stricto wall was similar across the three cell morphologies, with exception in the chitin content, which was significantly different in the three morphologies. The cell wall from germlings showed lower rhamnose content and higher glucose levels than other cell morphologies. In S. brasiliensis, the wall sugars were constant in the three morphologies, but glucose was lower in yeast-like cells. In S. schenckii sensu stricto cells most of chitin and ß1,3-glucan were underneath wall components, but in S. brasiliensis germlings, chitin was exposed at the cell surface, and ß1,3-glucan was found in the outer part of the conidia wall. We also compared the ability of these cells to stimulate cytokine production by human peripheral blood mononuclear cells. The three S. schenckii sensu stricto morphologies stimulated increased levels of pro-inflammatory cytokines, when compared to S. brasiliensis cells; while the latter, with exception of conidia, stimulated higher IL-10 levels. Dectin-1 was a key receptor for cytokine production during stimulation with the three morphologies of S. schenckii sensu stricto, but dispensable for cytokine production stimulated by S. brasiliensis germlings. TLR2 and TLR4 were also involved in the sensing of Sporothrix cells, with a major role for the former during cytokine stimulation. Mannose receptor had a minor contribution during cytokine stimulation by S. schenckii sensu stricto yeast-like cells and germlings, but S. schenckii sensu stricto conidia and S. brasiliensis yeast-like cells stimulated pro-inflammatory cytokines via this receptor. In conclusion, S. brasiliensis and S. schenckii sensu stricto, have similar wall composition, which undergoes changes depending on the cell morphology. These differences in the cell wall composition, are likely to influence the contribution of immune receptors during cytokine stimulation by human monocytes.

20.
Planta ; 245(2): 265-281, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27730409

RESUMEN

MAIN CONCLUSION: Biosynthesis of agave fructans occurs in mesontle vacuoles which showed fluctuations in FAZY activities and synthesized a diverse spectrum of fructooligosaccharide isomers. Agave tequilana Weber Blue variety is an important agronomic crop in Mexico. Fructan metabolism in A. tequilana exhibits changes in fructan content, type, degree of polymerization (DP), and molecular structure. Specific activities of vacuolar fructan active enzymes (FAZY) in A. tequilana plants of different age and the biosynthesis of fructooligosaccharides (FOSs) were analyzed in this work. Vacuoles from mesontle (stem) protoplasts were isolated and collected from 2- to 7-year-old plants. For the first time, agave fructans were identified in the vacuolar content by HPAEC-PAD. Several FAZY activities (1-SST, 6-SFT, 6G-FFT, 1-FFT, and FEH) with fluctuations according to the plant age were found in protein vacuolar extracts. Among vacuolar FAZY, 1-SST activities appeared in all plant developmental stages, as well as 1-FFT and FEH activities. The enzymes 6G-FFT and 6-SST showed only minimal activities. Lowest and highest FAZY activities were found in 2- and 6-year-old plants, respectively. Synthesized products (FOS) were analyzed by TLC and HPAEC-PAD. Vacuolar FAZYs yielded large FOS isomers diversity, being 7-year-old plants the ones that synthesized a greater variety of fructans with different DP, linkages, and molecular structures. Based on the above, we are proposing a model for the FAZY activities constituting the FOS biosynthetic pathways in Agave tequilana Weber Blue variety.


Asunto(s)
Agave/fisiología , Oligosacáridos/biosíntesis , Proteínas de Plantas/metabolismo , Vacuolas/metabolismo , Agave/metabolismo , Conformación de Carbohidratos , Metabolismo de los Hidratos de Carbono , Fructanos/metabolismo , Glicósido Hidrolasas/metabolismo , Hexosiltransferasas/metabolismo , Oligosacáridos/análisis , Oligosacáridos/química , Factores de Tiempo
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