RESUMEN
Marine algae are a major source of ω-3 long-chain polyunsaturated fatty acids (ω3-LCPUFAs), which are conditionally essential nutrients in humans and a target for industrial production. The biosynthesis of these molecules in marine algae requires the desaturation of fatty acids by Δ6-desaturases, and enzymes from different species display a range of specificities toward ω3- and ω6-LCPUFA precursors. In the absence of a molecular structure, the structural basis for the variable substrate specificity of Δ6-desaturases is poorly understood. Here we have conducted a consensus mutagenesis and ancestral protein reconstruction-based analysis of the Δ6-desaturase family, focusing on the ω3-specific Δ6-desaturase from Micromonas pusilla (MpΔ6des) and the bispecific (ω3/ω6) Δ6-desaturase from Ostreococcus tauri (OtΔ6des). Our characterization of consensus amino acid substitutions in MpΔ6des revealed that residues in diverse regions of the protein, such as the N-terminal cytochrome b5 domain, can make important contributions to determining substrate specificity. Ancestral protein reconstruction also suggests that some extant Δ6-desaturases, such as OtΔ6des, could have adapted to different environmental conditions by losing specificity for ω3-LCPUFAs. This data set provides a map of regions within Δ6-desaturases that contribute to substrate specificity and could facilitate future attempts to engineer these proteins for use in biotechnology.
Asunto(s)
Chlorophyta/enzimología , Linoleoil-CoA Desaturasa/química , Linoleoil-CoA Desaturasa/genética , Chlorophyta/química , Chlorophyta/clasificación , Chlorophyta/genética , Ácidos Grasos Omega-3/química , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-6/química , Ácidos Grasos Omega-6/metabolismo , Linoleoil-CoA Desaturasa/metabolismo , Familia de Multigenes , Mutagénesis , Filogenia , Conformación Proteica , Especificidad por SustratoRESUMEN
Alpha-linolenic acid (ALA, 18:3Δ9,12,15) and γ-linolenic acid \ (GLA, 18:3Δ6,9,12) are important trienoic fatty acids, which are beneficial for human health in their own right, or as precursors for the biosynthesis of long-chain polyunsaturated fatty acids. ALA and GLA in seed oil are synthesized from linoleic acid (LA, 18:2Δ9,12) by the microsomal ω-3 fatty acid desaturase (FAD3) and Δ6 desaturase (D6D), respectively. Cotton (Gossypium hirsutum L.) seed oil composition was modified by transforming with an FAD3 gene from Brassica napus and a D6D gene from Echium plantagineum, resulting in approximately 30% ALA and 20% GLA, respectively. The total oil content in transgenic seeds remained unaltered relative to parental seeds. Despite the use of a seed-specific promoter for transgene expression, low levels of GLA and increased levels of ALA were found in non-seed cotton tissues. At low temperature, the germinating cottonseeds containing the linolenic acid isomers elongated faster than the untransformed controls. ALA-producing lines also showed higher photosynthetic rates at cooler temperature and better fiber quality compared to both untransformed controls and GLA-producing lines. The oxidative stability of the novel cottonseed oils was assessed, providing guidance for potential food, pharmaceutical and industrial applications of these oils.
Asunto(s)
Fibra de Algodón , Aceite de Semillas de Algodón/metabolismo , Germinación/genética , Gossypium/genética , Fotosíntesis/genética , Semillas/crecimiento & desarrollo , Ácido alfa-Linolénico/metabolismo , Ácido gammalinolénico/metabolismo , Brassica napus/genética , Respuesta al Choque por Frío , Fibra de Algodón/normas , Ácido Graso Desaturasas/genética , Ácido Graso Desaturasas/metabolismo , Ingeniería Genética , Gossypium/metabolismo , Plantas Modificadas Genéticamente , Semillas/metabolismo , Ácido alfa-Linolénico/genética , Ácido gammalinolénico/genéticaRESUMEN
Alternative bone regeneration strategies that do not rely on harvested tissue or exogenous growth factors are needed. One of the major challenges in tissue reconstruction is recreating the bone tissue microenvironment using the appropriate combination of cells, scaffold, and stimulation to direct differentiation. This study presents a bone regeneration formulation that involves the use of human adipose-derived mesenchymal stem cells (hASCs) and a three-dimensional (3D) hydrogel scaffold based on self-assembled RADA16 peptides containing superparamagnetic iron oxide nanoparticles (NPs). Although superparamagnetic NPs could be used as stimulus to manipulate the cell proliferation and differentiation, in this paper their use is explored for assisting osteogenic differentiation of hASCs in conjunction with direct stimulation by extremely low-frequency pulsed electromagnetic fields (pEMFs). Cellular morphology, proliferation, and viability, as well as alkaline phosphatase activity, calcium deposition, and osteogenic capacity were monitored for cells cultured up to 21 days in the 3D construct. The results show that the pEMFs and NPs do not have any negative effect on cell viability, but instead distinctly induced early differentiation of hASCs to an osteoblastic phenotype, when compared with cells without biophysical stimulation. This effect is attributed to synergy between the pEMFs and NPs, which may have stimulated mechanotransduction pathways, which, in turn activated biochemical signals between cells to differentiate or proliferate. This approach may offer a safe and effective option for the treatment of non-union bone fractures. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.
Asunto(s)
Campos Electromagnéticos , Células Madre Mesenquimatosas/citología , Andamios del Tejido , Fosfatasa Alcalina/metabolismo , Regeneración Ósea , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Hidrogeles , Nanopartículas Magnéticas de Óxido de Hierro/química , Células Madre Mesenquimatosas/fisiología , Osteoblastos/citología , Osteoblastos/fisiología , Osteogénesis , Péptidos/químicaRESUMEN
Cocos nucifera (coconut), a member of the Arecaceae family, is an economically important woody palm that is widely grown in tropical and subtropical regions. The coconut palm is well known for its ability to accumulate large amounts of oil, approximately 63% of the seed weight. Coconut oil varies significantly from other vegetable oils as it contains a high proportion of medium-chain fatty acids (MCFA; 85%). The unique composition of coconut oil raises interest in understanding how the coconut palm produces oil of a high saturated MCFA content, and if such an oil profile could be replicated via biotechnology interventions. Although some gene discovery work has been performed there is still a significant gap in the knowledge associated with coconut's oil production pathways. In this study, a de novo transcriptome was assembled for developing coconut endosperm to identify genes involved in the synthesis of lipids, particularly triacylglycerol. Of particular interest were thioesterases, acyltransferases and oleosins because of their involvement in the processes of releasing fatty acids for assembly, esterification of fatty acids into glycerolipids and protecting oils from degradation, respectively. It is hypothesized that some of these genes may exhibit a strong substrate preference for MCFA and hence may assist the future development of vegetable oils with an enriched MCFA composition. In this study, we identified and confirmed functionality of five candidate genes from the gene families of interest. This study will benefit future work in areas of increasing vegetable oil production and the tailoring of oil fatty acid compositions.
Asunto(s)
Endospermo/metabolismo , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Transcriptoma/genética , Ácidos Grasos/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Metabolismo de los Lípidos/genética , Metabolismo de los Lípidos/fisiología , Proteínas de Plantas/genética , Nicotiana/genética , Triglicéridos/metabolismoRESUMEN
Synthesis and accumulation of the storage lipid triacylglycerol in vegetative plant tissues has emerged as a promising strategy to meet the world's future need for vegetable oil. Sorghum (Sorghum bicolor) is a particularly attractive target crop given its high biomass, drought resistance and C4 photosynthesis. While oilseed-like triacylglycerol levels have been engineered in the C3 model plant tobacco, progress in C4 monocot crops has been lagging behind. In this study, we report the accumulation of triacylglycerol in sorghum leaf tissues to levels between 3 and 8.4% on a dry weight basis depending on leaf and plant developmental stage. This was achieved by the combined overexpression of genes encoding the Zea mays WRI1 transcription factor, Umbelopsis ramanniana UrDGAT2a acyltransferase and Sesamum indicum Oleosin-L oil body protein. Increased oil content was visible as lipid droplets, primarily in the leaf mesophyll cells. A comparison between a constitutive and mesophyll-specific promoter driving WRI1 expression revealed distinct changes in the overall leaf lipidome as well as transitory starch and soluble sugar levels. Metabolome profiling uncovered changes in the abundance of various amino acids and dicarboxylic acids. The results presented here are a first step forward towards the development of sorghum as a dedicated biomass oil crop and provide a basis for further combinatorial metabolic engineering.
Asunto(s)
Lípidos/biosíntesis , Hojas de la Planta/metabolismo , Aceites de Plantas/análisis , Sorghum/metabolismo , Aminoácidos/análisis , Aminoácidos/metabolismo , Metabolismo de los Lípidos , Lípidos/análisis , Hojas de la Planta/química , Aceites de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Sorghum/química , Almidón/análisis , Almidón/metabolismo , Triglicéridos/metabolismo , Regulación hacia ArribaRESUMEN
Vegetable oils extracted from oilseeds are an important component of foods, but are also used in a range of high value oleochemical applications. Despite being biodegradable, nontoxic and renewable current plant oils suffer from the presence of residual polyunsaturated fatty acids that are prone to free radical formation that limit their oxidative stability, and consequently shelf life and functionality. Many decades of plant breeding have been successful in raising the oleic content to ~90%, but have come at the expense of overall field performance, including poor yields. Here, we engineer superhigh oleic (SHO) safflower producing a seed oil with 93% oleic generated from seed produced in multisite field trials spanning five generations. SHO safflower oil is the result of seed-specific hairpin-based RNA interference of two safflower lipid biosynthetic genes, FAD2.2 and FATB, producing seed oil containing less than 1.5% polyunsaturates and only 4% saturates but with no impact on lipid profiles of leaves and roots. Transgenic SHO events were compared to non-GM safflower in multisite trial plots with a wide range of growing season conditions, which showed no evidence of impact on seed yield. The oxidative stability of the field-grown SHO oil produced from various sites was 50 h at 110°C compared to 13 h for conventional ~80% oleic safflower oils. SHO safflower produces a uniquely stable vegetable oil across different field conditions that can provide the scale of production that is required for meeting the global demands for high stability oils in food and the oleochemical industry.
Asunto(s)
Carthamus tinctorius/metabolismo , Ácidos Oléicos/metabolismo , Interferencia de ARN , Aceite de Cártamo/química , Semillas/metabolismo , Carthamus tinctorius/genética , Oxidación-ReducciónRESUMEN
Despite several advancements in the biomedical sciences, an efficient cancer therapy still remains a challenge. Nanomedicines have shown potential to overcome certain roadblocks faced in the existing treatment modalities. Losartan potassium (LP) which is a known vasodilator also exhibits anti fibrolytic and anti-metastatic properties altogether. Further, also being a potential angiotensin II type 1 receptor antagonist, it has been well explored for down regulating tumourogenic biomarkers like VEGF-A (Vascular endothelial growth factor A) and suppression of neovascularization, making it a suitable drug to target for cancer treatment. Besides this, it too reflected the stimulation of pro apoptotic signaling pathways. But due to its lower bioavailability and extensive hepatic metabolism its therapeutic index reduces down. Thus, the present study is focused on designing a nano-delivery system using graphene oxide (GO) as a nano-vehicle and conjugated the LP with it. Then, the successful synthesis of GO and GO-LP nano conjugates were characterized by high-resolution transmission electron microscopy, X-ray diffraction, FTIR and UV visible spectroscopy, confirming the formation of nanosheets. The qualitative morphological evaluation of NB41A3 neuroblastoma cell line treated with bare GO, LP and GO-LP using microscopy and DAPI staining revealed the inhibitory action of GO-LP nano conjugate on cell proliferation. Additionally, the cytotoxicity was also estimated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), Nitric oxide (NO) and Lactate dehydrogenase (LDH) assays. The results show that GO-LP significantly suppresses the cell viability in comparison to control and bare GO suggesting that the designed system may express its potential to be used with existing chemo drugs for the treatment of neural cancers.
Asunto(s)
Antineoplásicos/uso terapéutico , Grafito/uso terapéutico , Losartán/uso terapéutico , Nanoconjugados/uso terapéutico , Neuroblastoma/tratamiento farmacológico , Bloqueadores del Receptor Tipo 1 de Angiotensina II/química , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Animales , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Grafito/química , Losartán/análogos & derivados , Ratones , Nanoconjugados/químicaRESUMEN
The tuneability of oxygen containing groups in graphene oxide (GO) that controls physicochemical properties is highly desirable for device applications. In this context, the thermally reduced graphene oxide (r-GO) powders and spin coated thin films with varying sp2/sp3 carbon network have been prepared using highly exfoliated GO (synthesized using modified Hummer's method with an innovative conjunction of lyophilisation). The additional step of lyophilisation results in the formation of highly exfoliated and monodispersed GO nanosheets as evidenced from FESEM, TEM, XRD, and Raman, FT-IR and UV-Vis spectroscopy. Spectroscopic analysis revealed the systematic evolution of r-GO with tuneable structural, optical and electrical properties as results of varying annealing temperatures (100-400 °C), due to restoration of sp2 conducting carbon network i.e., the formation of new -CâC- network and Stones-Wales defect. The tuneability of physical properties is further corroborated by change in the resistance values, as evidenced through the current-voltage characteristics in GO thin film based lateral device structures with Ag and Al top contacts. Controlling physicochemical properties at relatively low processing temperature warrants the utilization of GO and r-GO in various electronic and optoelectronic devices.
RESUMEN
Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional cotton seed oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of cotton seed oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed-specific RNAi-mediated down-regulation of ß-ketoacyl-ACP synthase II (KASII) catalysing the elongation of palmitoyl-ACP to stearoyl-ACP has succeeded in dramatically increasing the C16 fatty acid content of cotton seed oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in oil content in these high-palmitic (HP) lines, seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn-2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high-oleic (HO) and high-stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.
Asunto(s)
3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/genética , Aceite de Semillas de Algodón/análisis , Regulación hacia Abajo , Mejoramiento Genético , Gossypium/enzimología , Gossypium/genética , Ácido Palmítico/análisis , Interferencia de ARN , Agrobacterium tumefaciens/genética , Secuencia de Bases , Aceite de Semillas de Algodón/química , Ácidos Grasos/análisis , Ácidos Grasos/química , Ácidos Grasos Monoinsaturados/química , Silenciador del Gen , Genes de Plantas , Vectores Genéticos , Genotipo , Germinación , Lípidos/análisis , Lípidos/química , Estrés Oxidativo , Ácido Palmítico/química , Fosfatidilcolinas/análisis , Filogenia , Aceites de Plantas/análisis , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/metabolismo , Semillas/genética , Alineación de Secuencia , Ácidos Esteáricos/análisis , Transformación Genética , Triglicéridos/análisisRESUMEN
Medium-chain fatty acids (MCFA, C6-14 fatty acids) are an ideal feedstock for biodiesel and broader oleochemicals. In recent decades, several studies have used transgenic engineering to produce MCFA in seeds oils, although these modifications result in unbalance membrane lipid profiles that impair oil yields and agronomic performance. Given the ability to engineer nonseed organs to produce oils, we have previously demonstrated that MCFA profiles can be produced in leaves, but this also results in unbalanced membrane lipid profiles and undesirable chlorosis and cell death. Here we demonstrate that the introduction of a diacylglycerol acyltransferase from oil palm, EgDGAT1, was necessary to channel nascent MCFA directly into leaf oils and therefore bypassing MCFA residing in membrane lipids. This pathway resulted in increased flux towards MCFA rich leaf oils, reduced MCFA in leaf membrane lipids and, crucially, the alleviation of chlorosis. Deep sequencing of African oil palm (Elaeis guineensis) and coconut palm (Cocos nucifera) generated candidate genes of interest, which were then tested for their ability to improve oil accumulation. Thioesterases were explored for the production of lauric acid (C12:0) and myristic (C14:0). The thioesterases from Umbellularia californica and Cinnamomum camphora produced a total of 52% C12:0 and 40% C14:0, respectively, in transient leaf assays. This study demonstrated that the introduction of a complete acyl-CoA-dependent pathway for the synthesis of MFCA-rich oils avoided disturbing membrane homoeostasis and cell death phenotypes. This study outlines a transgenic strategy for the engineering of biomass crops with high levels of MCFA rich leaf oils.
Asunto(s)
Arecaceae/genética , Arecaceae/metabolismo , Diacilglicerol O-Acetiltransferasa/genética , Ácidos Grasos/metabolismo , Hojas de la Planta/metabolismo , Aceites de Plantas/metabolismo , Arabidopsis/genética , Arecaceae/enzimología , Biomasa , Muerte Celular , Cinnamomum camphora/genética , Cocos/genética , Diacilglicerol O-Acetiltransferasa/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácidos Láuricos/metabolismo , Metabolismo de los Lípidos , Lípidos de la Membrana/metabolismo , Plantas Modificadas Genéticamente , Nicotiana/genética , Nicotiana/metabolismo , Transcriptoma , TriglicéridosRESUMEN
Synthesis and accumulation of plant oils in the entire vegetative biomass offers the potential to deliver yields surpassing those of oilseed crops. However, current levels still fall well short of those typically found in oilseeds. Here we show how transcriptome and biochemical analyses pointed to a futile cycle in a previously established Nicotiana tabacum line, accumulating up to 15% (dry weight) of the storage lipid triacylglycerol in leaf tissue. To overcome this metabolic bottleneck, we either silenced the SDP1 lipase or overexpressed the Arabidopsis thaliana LEC2 transcription factor in this transgenic background. Both strategies independently resulted in the accumulation of 30-33% triacylglycerol in leaf tissues. Our results demonstrate that the combined optimization of de novo fatty acid biosynthesis, storage lipid assembly and lipid turnover in leaf tissue results in a major overhaul of the plant central carbon allocation and lipid metabolism. The resulting further step changes in oil accumulation in the entire plant biomass offers the possibility of delivering yields that outperform current oilseed crops.
Asunto(s)
Mejoramiento Genético/métodos , Ingeniería Metabólica/métodos , Redes y Vías Metabólicas/fisiología , Nicotiana/fisiología , Hojas de la Planta/fisiología , Aceites de Plantas/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Aceites de Plantas/aislamiento & purificación , Factores de Transcripción/genéticaRESUMEN
Chinese tallow (Triadica sebifera) is a valuable oilseed-producing tree that can grow in a variety of conditions without competing for food production, and is a promising biofuel feedstock candidate. The fruits are unique in that they contain both saturated and unsaturated fat present in the tallow and seed layer, respectively. The tallow layer is poorly studied and is considered only as an external fatty deposition secreted from the seed. In this study we show that tallow is in fact a non-seed cellular tissue capable of triglyceride synthesis. Knowledge of lipid synthesis and storage mechanisms in tissues other than seed is limited but essential to generate oil-rich biomass crops. Here, we describe the annotated transcriptome assembly generated from the fruit coat, tallow and seed tissues of Chinese tallow. The final assembly was functionally annotated, allowing for the identification of candidate genes and reconstruction of lipid pathways. A tallow tissue-specific paralog for the transcription factor gene WRINKLED1 (WRI1) and lipid droplet-associated protein genes, distinct from those expressed in seed tissue, were found to be active in tallow, underpinning the mode of oil synthesis and packaging in this tissue. Our data have established an excellent knowledge base that can provide genetic and biochemical insights for engineering non-seed tissues to accumulate large amounts of oil. In addition to the large data set of annotated transcripts, the study also provides gene-based simple sequence repeat and single nucleotide polymorphism markers.
Asunto(s)
Euphorbiaceae/genética , Ácidos Grasos/metabolismo , Aceites de Plantas/metabolismo , Transcriptoma , Biocombustibles , Euphorbiaceae/metabolismo , Euphorbiaceae/ultraestructura , Ácidos Grasos/análisis , Frutas/genética , Frutas/metabolismo , Frutas/ultraestructura , Regulación de la Expresión Génica de las Plantas , Secuenciación de Nucleótidos de Alto Rendimiento , Metabolismo de los Lípidos , Lípidos/análisis , Anotación de Secuencia Molecular , Especificidad de Órganos , Aceites de Plantas/análisis , Proteínas de Plantas/genética , Semillas/genética , Semillas/metabolismo , Semillas/ultraestructura , Análisis de Secuencia de ADNRESUMEN
Transgenic engineering of plants is important in both basic and applied research. However, the expression of a transgene can dwindle over time as the plant's small (s)RNA-guided silencing pathways shut it down. The silencing pathways have evolved as antiviral defence mechanisms, and viruses have co-evolved viral silencing-suppressor proteins (VSPs) to block them. Therefore, VSPs have been routinely used alongside desired transgene constructs to enhance their expression in transient assays. However, constitutive, stable expression of a VSP in a plant usually causes pronounced developmental abnormalities, as their actions interfere with endogenous microRNA-regulated processes, and has largely precluded the use of VSPs as an aid to stable transgene expression. In an attempt to avoid the deleterious effects but obtain the enhancing effect, a number of different VSPs were expressed exclusively in the seeds of Arabidopsis thaliana alongside a three-step transgenic pathway for the synthesis of arachidonic acid (AA), an ω-6 long chain polyunsaturated fatty acid. Results from independent transgenic events, maintained for four generations, showed that the VSP-AA-transformed plants were developmentally normal, apart from minor phenotypes at the cotyledon stage, and could produce 40% more AA than plants transformed with the AA transgene cassette alone. Intriguingly, a geminivirus VSP, V2, was constitutively expressed without causing developmental defects, as it acts on the siRNA amplification step that is not part of the miRNA pathway, and gave strong transgene enhancement. These results demonstrate that VSP expression can be used to protect and enhance stable transgene performance and has significant biotechnological application.
Asunto(s)
Arabidopsis/genética , Silenciador del Gen , Ingeniería Genética , Redes y Vías Metabólicas/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Ácido Araquidónico/metabolismo , Aceites de Plantas/metabolismo , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Proteínas Virales/genéticaRESUMEN
High biomass crops have recently attracted significant attention as an alternative platform for the renewable production of high energy storage lipids such as triacylglycerol (TAG). While TAG typically accumulates in seeds as storage compounds fuelling subsequent germination, levels in vegetative tissues are generally low. Here, we report the accumulation of more than 15% TAG (17.7% total lipids) by dry weight in Nicotiana tabacum (tobacco) leaves by the co-expression of three genes involved in different aspects of TAG production without severely impacting plant development. These yields far exceed the levels found in wild-type leaf tissue as well as previously reported engineered TAG yields in vegetative tissues of Arabidopsis thaliana and N. tabacum. When translated to a high biomass crop, the current levels would translate to an oil yield per hectare that exceeds those of most cultivated oilseed crops. Confocal fluorescence microscopy and mass spectrometry imaging confirmed the accumulation of TAG within leaf mesophyll cells. In addition, we explored the applicability of several existing oil-processing methods using fresh leaf tissue. Our results demonstrate the technical feasibility of a vegetative plant oil production platform and provide for a step change in the bioenergy landscape, opening new prospects for sustainable food, high energy forage, biofuel and biomaterial applications.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Ingeniería Metabólica , Nicotiana/metabolismo , Aceites de Plantas/metabolismo , Triglicéridos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Biocombustibles , Biomasa , Diacilglicerol O-Acetiltransferasa/genética , Diacilglicerol O-Acetiltransferasa/metabolismo , Ácidos Grasos/análisis , Ácidos Grasos/metabolismo , Expresión Génica , Fenotipo , Hojas de la Planta/metabolismo , Aceites de Plantas/análisis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Factores de Tiempo , Nicotiana/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transgenes , Triglicéridos/análisisRESUMEN
The development of antibiotics has played a significant role in combating the dreaded infectious disease such as tuberculosis, pneumonia, typhoid fever and meningitis in 20th century. However, the improper use of antibiotics led to the development of multidrug resistance (MDR) in microbial flora raising a global public health concern of 21st century. This unforeseen threat demands the development of new drugs and strategies for combating antibiotic resistance shown by many microbial species. Recent developments in nanotechnology to engineer nanoparticles with desired physicochemical properties have been projected as a new line of defense against MDR micro-organism. In this review, we summarized and discussed the recent development demonstrating the potential of nanomaterials to evade the MDR. Nanoparticles have shown effective antimicrobial activity against MDR bacteria, such as Acinetobacter baumanii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Mycobacterium tuberculosis, vancomycin resistant enterococci, methicillin-resistant Staphylococcus aureus and others. Furthermore, new strategies like combination of radiation and drugs with nanoparticle that are being explored to potentiate the effectiveness against MDR bacteria have also been summarized.
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Infecciones Bacterianas/tratamiento farmacológico , Fenómenos Fisiológicos Bacterianos/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/fisiología , Nanopartículas/administración & dosificación , Animales , Antibacterianos/administración & dosificación , Antibacterianos/síntesis química , Supervivencia Celular/efectos de los fármacos , Humanos , Nanopartículas/química , Tamaño de la PartículaRESUMEN
In the present global context, continuous blood pressure (BP) monitoring is paramount in addressing the global mortality rates attributed to hypertension. Achieving precise insights into the human cardiovascular system necessitates accurate measurement of BP, and the accuracy depends on the faithful recording of oscillations or pulsations. This task ultimately depends on the caliber of the pressure sensor embedded in the BP device. In this context, we have fabricated a flexible resistive pressure sensor based on reduced graphene oxide (rGO) and a polydimethylsiloxane (PDMS) sponge that is highly flexible and sensitive. The designed device operates effectively with a minimal bias voltage of 500 mV, at which point it showed its maximum relative change in current, reaching approximately 25%. Additionally, the sensing device showed a notable change in resistance values, exhibiting almost 100% change in resistance when subjected to a pressure of 400 mmHg and high sensitivity of 0.27 mmHg-1. After promising outcomes were obtained during static pressure measurement, the sensor was used for BP monitoring in humans. The sensor accurately traced the oscillometric waveform (OMW) for distinct systolic blood pressure (SBP) and diastolic blood pressure (DBP) combinations to cover a range of medical situations, including hypotension, standard or normal, and hypertension. The values of SBP, DBP, and MAP were derived from the sensor's output using the MAA technique, and the errors in these values concerning the simulator and the traditional BP monitor follow the universal AAMI/ESH/ISO protocols. Bland-Altman (B&A) correlation and scatter plots were used to compare the sensor's results and further validate the proposed sensor. The sensor showed the mean and standard deviation error in the SBP, DBP, and MBP of -0.2 ± 5.9, -0.5 ± 7, and -0.9 ± 4.7 mmHg when compared with the noninvasive blood pressure (NIBP) simulator. The pulse rate (PR) was also calculated from the same OMW for the specified value of 80 beats per minute (bpm) given by the simulator and reported a mean PR value of â¼81 bpm, close to the reference value. The findings show that the flexible resistive sensing device can accurately measure BP and replace the existing sensors of BP devices.
RESUMEN
Context: Worldwide malnutrition is identified as a major health and nutrition problem. Undernutrition contributes to an estimated 45% of child deaths globally. The prevalence of underweight among children in India is among the highest in the world. Our children also bear a tremendous double burden of malnutrition. Aims: To find out the prevalence and determinants of malnutrition among six months to three-year-old children in the rural community of Northern India. Settings and Design: A community-based cross-sectional study conducted among children aged six months to three years in a rural area of Ludhiana district, Methods and Material: A total of 662 children in the age group of six months to three years from a population of 30,000 were identified and included in the study. All the relevant information regarding these children was collected from family folders. Socioeconomic status was assessed using the modified Udai Pareek scale (MUP). Statistical analysis used: The data collected was entered in MS Excel and was analyzed using SPSS version 26 and WHO Anthro Survey Analyzer. Results: Out of 662 children, 16% were underweight. Almost 50% of the children in the two-three years category were underweight. The prevalence of stunting in the study population was 20.7% and that of overweight was 4.8%. The prevalence of underweight was higher in children of low socioeconomic status than in children from upper socioeconomic status (P = 0.000). There was a significant association between birth order and increasing cases of underweight (P = 0.000). Conclusions: The causes of malnutrition in children are complex and involve multiple factors. There is a need for vigorous monitoring for early detection of malnutrition for children aged two-three years. The improvement of maternal education will improve the nutritional status of the child.
RESUMEN
Rationally designed multitargeted drugs, known as network therapeutics/multimodal drugs, have emerged as versatile therapeutic solutions to combat drug-resistant microbes. Here, we report novel mechanistic insights into cellular and molecular targets of ZnO quantum dots (QDs) against Candida albicans, a representative of fungal pathogens. Stable, monodispersed 4-6 nm ZnO QDs were synthesized using a wet chemical route, which exhibited dose-dependent inhibition on the growth dynamics of Candida. Treatment with 200 µg/mL ZnO QDs revealed an aberrant morphology and a disrupted cellular ultrastructure in electron microscopy and led to a 23% reduction in ergosterol content and a 53% increase in intracellular reactive oxygen species. Significant increase in steady-state fluorescence polarization and fluorescence lifetime decay of membrane probe 1,6-diphenyl-1,3,5-hexatriene (DPH) in treated cells, respectively, implied reduction in membrane fluidity and enhanced microviscosity. The observed reduction in passive diffusion of fluorescent Rhodamine 6G across the membrane validated the intricate relationship between ergosterol, membrane fluidity, and microviscosity. An inverse relationship existing between ergosterol biosynthetic genes, ERG11 and ERG3 in treated cells, related well with displayed higher susceptibilities. Furthermore, treated cells exhibited impaired functionality and downregulation of ABC drug efflux pumps. Multiple cellular targets of ZnO QDs in Candida were validated by in silico molecular docking. Thus, targeting ERG11, ERG3, and ABC drug efflux pumps might emerge as a versatile, nano-ZnO-based strategy in fungal therapeutics to address the challenges of drug resistance.
Asunto(s)
Antifúngicos , Candida albicans , Ergosterol , Puntos Cuánticos , Óxido de Zinc , Puntos Cuánticos/química , Candida albicans/efectos de los fármacos , Óxido de Zinc/farmacología , Óxido de Zinc/química , Antifúngicos/farmacología , Antifúngicos/química , Especies Reactivas de Oxígeno/metabolismo , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento MolecularRESUMEN
BACKGROUND: The application and nutritional value of vegetable oil is highly dependent on its fatty acid composition, especially the relative proportion of its two major fatty acids, i.e oleic acid and linoleic acid. Microsomal oleoyl phosphatidylcholine desaturase encoded by FAD2 gene is known to introduce a double bond at the Δ12 position of an oleic acid on phosphatidylcholine and convert it to linoleic acid. The known plant FAD2 enzymes are encoded by small gene families consisting of 1-4 members. In addition to the classic oleate Δ12-desaturation activity, functional variants of FAD2 that are capable of undertaking additional or alternative acyl modifications have also been reported in a limited number of plant species. In this study, our objective was to identify FAD2 genes from safflower and analyse their differential expression profile and potentially diversified functionality. RESULTS: We report here the characterization and functional expression of an exceptionally large FAD2 gene family from safflower, and the temporal and spatial expression profiles of these genes as revealed through Real-Time quantitative PCR. The diversified functionalities of some of the safflower FAD2 gene family members were demonstrated by ectopic expression in yeast and transient expression in Nicotiana benthamiana leaves. CtFAD2-1 and CtFAD2-10 were demonstrated to be oleate desaturases specifically expressed in developing seeds and flower head, respectively, while CtFAD2-2 appears to have relatively low oleate desaturation activity throughout the plant. CtFAD2-5 and CtFAD2-8 are specifically expressed in root tissues, while CtFAD2-3, 4, 6, 7 are mostly expressed in the cotyledons and hypocotyls in young safflower seedlings. CtFAD2-9 was found to encode a novel desaturase operating on C16:1 substrate. CtFAD2-11 is a tri-functional enzyme able to introduce a carbon double bond in either cis or trans configuration, or a carbon triple (acetylenic) bond at the Δ12 position. CONCLUSIONS: In this study, we isolated an unusually large FAD2 gene family with 11 members from safflower. The seed expressed FAD2 oleate Δ12 desaturase genes identified in this study will provide candidate targets to manipulate the oleic acid level in safflower seed oil. Further, the divergent FAD2 enzymes with novel functionality could be used to produce rare fatty acids, such as crepenynic acid, in genetically engineered crop plants that are precursors for economically important phytoalexins and oleochemical products.