Non-vesicular lipid transfer at ER and plasma membrane (PM) contact sites (CS) is crucial for the... more Non-vesicular lipid transfer at ER and plasma membrane (PM) contact sites (CS) is crucial for the maintenance of membrane lipid homeostasis. Extended synaptotagmins (E-Syts) play a central role in this process as they act as molecular tethers of ER and PM and as lipid transfer proteins between these organelles. E-Syts are proteins constitutively anchored to the ER through an N-terminal hydrophobic segment and bind the PM via a variable number of C-terminal C2 domains. Synaptotagmins (SYTs) are the plant orthologous of E-Syts and regulate the ER–PM communication in response to abiotic stress. Combining different structural and biochemical techniques, we demonstrate that the binding of SYT1 to lipids occurs through a Ca2+-dependent lipid-binding site and by a site for phosphorylated forms of phosphatidylinositol, thus integrating two different molecular signals in response to stress. In addition, we show that SYT1 displays three highly flexible hinge points that provide conformational...
17th Euro Fed Lipid Congress 20-23 October 2019, Seville, SpainCastor plant produces seeds rich i... more 17th Euro Fed Lipid Congress 20-23 October 2019, Seville, SpainCastor plant produces seeds rich in ricinoleic acid (80 to 90%), an hydroxylated fatty acid, and with up to 60% oil. Castor seed oil has many non-food applications, including the production of biolubricants, bioplastics, cosmetics, paintings and covers. Moreover, castor plant is a productive oil crop that is not demanding in terms of soil and water and can be growth in marginal lands. However, the high toxicity of the seeds has always been an important burden at the time of manage large productions of this crop. Castor seed oil synthesis have been object of intensive research, due this plant is able to accumulate large amounts of one specific fatty acid, so the metabolic machinery associated to this fact is of a great interest because it can give information about how to make oil crops to accumulate single fatty acids. The research on castor seed biosynthetic machinery and biotechnology have been always hampered by the lack of a standard protocol of castor plant transformation. In this regard, in the present work we developed straightforward and reliable procedures enabling the transient and permanent transformation of castor plant. Transient transformation made possible to quick assessment of genetic constructions and testing different promoters in this species. Furthermore, permeant plants encoding for a silencing gene construct against castor hydroxylase were also developed. This plants produced seeds with lower levels of ricinoleic acid and a considerable reduction of the oil content. The comparison of this phenotype with the wild type plant and the OLE-1 high oleic castor seed mutant gave interesting insights of the process of castor seed oil synthesis. The perspectives of making castor seed an oil biofactory in the future will be discussed at the view of results
The authors acknowledge the support by the Plan Propio from University of Malaga, Campus de Excel... more The authors acknowledge the support by the Plan Propio from University of Malaga, Campus de Excelencia Internacional de Andalucia and by the Redes of Excelencia (BIO2014-56153-REDT) and BIO2017-82609-R & BIO2014-55380-R of the Ministerio de Economia, Industria y Competitividad
e21660Background: Alopecia is a common side effect of chemotherapy (CT) used in the treatment of ... more e21660Background: Alopecia is a common side effect of chemotherapy (CT) used in the treatment of breast cancer, which affects drastically patients’ quality of life. "Dignicap" is the first scalp co...
Wax esters (WEs) and steryl esters (SEs) are minor components of sunflower oils formed by the est... more Wax esters (WEs) and steryl esters (SEs) are minor components of sunflower oils formed by the esterification of long chain fatty alcohols and sterols to fatty acids. These compounds have similar carbon numbers and polarities making them difficult to separate using conventional chromatographic methods. In this study, electrospray ionisation-tandem mass spectrometry (ESI-MS/MS) allowed the rapid and accurate profiling of WEs and SEs acyl moieties in total ester fractions of common and mutant sunflower oils with different fatty acid profiles. The acyl composition of both WEs and SEs partially reflected that of the oil and the high oleic background displayed the lowest level of crystallisable waxes. ESI-MS/MS complemented by GC-MS analyses revealed that SEs contain 17-30% of previously unreported methylsterol moieties. We demonstrated that these compounds are overlooked by official sterol analytical methods which may have consequences for quality control and authentication of vegetable ...
The functional characterization of wax biosynthetic enzymes in transgenic plants has opened the p... more The functional characterization of wax biosynthetic enzymes in transgenic plants has opened the possibility of producing tailored wax esters (WEs) in the seeds of a suitable host crop. In this study, in addition to systematically evaluating a panel of WE biosynthetic activities, we have also modulated the acyl-CoA substrate pool, through the co-expression of acyl-ACP thioesterases, to direct the accumulation of medium-chain fatty acids. Using this combinatorial approach, we determined the additive contribution of both the varied acyl-CoA pool and biosynthetic enzyme substrate specificity to the accumulation of non-native WEs in the seeds of transgenic Camelina plants. A total of fourteen constructs were prepared containing selected FAR and WS genes in combination with an acyl-ACP thioesterase. All enzyme combinations led to the successful production of wax esters, of differing compositions. The impact of acyl-CoA thioesterase expression on wax ester accumulation varied depending on ...
Revista panamericana de salud publica = Pan American journal of public health, 2016
Objective To document the prevalence of patients on hemodialysis in southwestern Guatemala who ha... more Objective To document the prevalence of patients on hemodialysis in southwestern Guatemala who have chronic kidney disease (CKD) of non-traditional causes (CKDnt). Methods This cross-sectional descriptive study interviewed patients on hemodialysis at the Instituto Guatemalteco de Seguridad Social on their health and occupational history. Laboratory serum, urine and vital sign data at the initiation of hemodialysis were obtained from chart reviews. Patients were classified according to whether they had hypertension or obesity or neither. The proportion of patients with and without these traditional CKD risk factors was recorded and the association between demographic and occupational factors and a lack of traditional CKD risk factors analyzed using multivariate logistic regression. Results Of 242 total patients (including 171 non-diabetics) enrolled in hemodialysis in southwestern Guatemala, 45 (18.6% of total patients and 26.3% of non-diabetics) lacked traditional CKD risk factors. ...
Resumen basado en ficha elaborada por los autores o la responsable. Entre el material anexo se en... more Resumen basado en ficha elaborada por los autores o la responsable. Entre el material anexo se encuentran presentaciones de diapositivas, y otros elementos elaborados durante el desarrollo
Fish currently supplies only 40% of the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA... more Fish currently supplies only 40% of the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) required to allow all individuals globally to meet the minimum intake recommendation of 500 mg/d. Therefore, alternative sustainable sources are needed. The main objective was to investigate the ability of genetically engineered Camelina sativa (20% EPA) oil (CO) to enrich tissue EPA and DHA relative to an EPA-rich fish oil (FO) in mammals. Six-week-old male C57BL/6J mice were fed for 10 wk either a palm oil-containing control (C) diet or diets supplemented with EPA-CO or FO, with the C, low-EPA CO (COL), high-EPA CO (COH), low-EPA FO (FOL), and high-EPA FO (FOH) diets providing 0, 0.4, 3.4, 0.3, and 2.9 g EPA/kg diet, respectively. Liver, muscle, and brain were collected for fatty acid analysis, and blood glucose and serum lipids were quantified. The expression of selected hepatic genes involved in EPA and DHA biosynthesis and in modulating their cellular impact was determined. The oi...
A recombinant camelina plant or cell comprising one or more polynucleotides encoding a Δ6-desatur... more A recombinant camelina plant or cell comprising one or more polynucleotides encoding a Δ6-desaturase, a Δ6-elongase and a Δ5-desaturase operably linked with one or more regulatory sequences.
La función de daño es el parámetro fundamental del modelo de Nivel de Daño Económico (NDE). Los o... more La función de daño es el parámetro fundamental del modelo de Nivel de Daño Económico (NDE). Los objetivos fueron: evaluar los perjuicios de Armadillidium vulgare en el cultivo de girasol y determinar la función de daño en el cultivo para poder estimar el NDE. Las evaluaciones se realizaron en tres ciclos agrícolas según un diseño en bloques completos aleatorizados con cinco repeticiones. Se sembraron ocho semillas de girasol y se infestaron con: 0 (testigo), 20, 40, 60, 80 y 120 individuos m-2 de A. vulgare en parcelas de 1m 2. Se evaluaron los perjuicios en hipocótile y cotiledones, número de plantas m-2 y el rendimiento. Se calcularon las funciones de daño (regresión entre la densidad de A. vulgare y la proporción de pérdida de rendimiento). Se observaron diferencias en la proporción de plantas con perjuicios severos en el hipocótile entre las densidades de A. vulgare. Esta categoría de perjuicio se correlacionó con la densidad de A. vulgare, con el número de plantas m-2 y con el rendimiento. Las funciones de daño representaron una proporción de pérdida de rendimiento de 0,0033 (R 2 = 0,64), 0,0023 (R 2 = 0,49) y 0,0048 (R 2 = 0,71) por individuo por metro cuadrado para los tres ciclos agrícolas, respectivamente. Cuando se combinaron todos los datos ésta fue de 0,0034 (R 2 = 0,59). Considerando valores económicos promedio, los NDE de A. vulgare en el cultivo de girasol variaron entre 22 y 81 individuos m-2. Teniendo en cuenta los coeficientes de determinación y que A. vulgare tiene hábitos alimenticios variables, la función de daño de 0,0033 es recomendable en el cálculo de NDE de A. vulgare en girasol.
Omega-3 fatty acids are characterized by a double bond at the third carbon atom from the end of t... more Omega-3 fatty acids are characterized by a double bond at the third carbon atom from the end of the carbon chain. Latterly, long chain polyunsaturated omega-3 fatty acids such as eicosapentaenoic acid (EPA; 20:5Δ5,8,11,14,17) and docosahexanoic acid (DHA; 22:6 Δ4,7,10,13,16,19), which typically only enter the human diet via the consumption of oily fish, have attracted much attention. The health benefits of the omega-3 LC-PUFAs EPA and DHA are now well established. Given the desire for a sustainable supply of omega-LC-PUFA, efforts have focused on enhancing the composition of vegetable oils to include these important fatty acids. Specifically, EPA and DHA have been the focus of much study, with the ultimate goal of producing a terrestrial plant-based source of these so-called fish oils. Over the last decade, many genes encoding the primary LC-PUFA biosynthetic activities have been identified and characterized. This has allowed the reconstitution of the LC-PUFA biosynthetic pathway in...
Anexo I: Normativas regulatorias de los estatutos docentes de las provincias. Argentina, 2010. Pr... more Anexo I: Normativas regulatorias de los estatutos docentes de las provincias. Argentina, 2010. Provincias Estatuto del Docente vigente en la provincia Año última modificación Buenos Aires
The role of acyl-CoA-dependent D6-desaturation in the heterologous synthesis of omega-3 long-chai... more The role of acyl-CoA-dependent D6-desaturation in the heterologous synthesis of omega-3 long-chain polyunsaturated fatty acids was systematically evaluated in transgenic yeast and Arabidopsis thaliana. The acyl-CoA D6-desaturase from the picoalga Ostreococcus tauri and orthologous activities from mouse (Mus musculus) and salmon (Salmo salar) were shown to generate substantial levels of D6-desaturated acyl-CoAs, in contrast to the phospholipid-dependent D6desaturases from higher plants that failed to modify this metabolic pool. Transgenic plants expressing the acyl-CoA D6-desaturases from either O. tauri or salmon, in conjunction with the two additional activities required for the synthesis of C20 polyunsaturated fatty acids, contained higher levels of eicosapentaenoic acid compared with plants expressing the borage phospholipid-dependent D6-desaturase. The use of acyl-CoA-dependent D6-desaturases almost completely abolished the accumulation of unwanted biosynthetic intermediates such as c-linolenic acid in total seed lipids. Expression of acyl-CoA D6-desaturases resulted in increased distribution of long-chain polyunsaturated fatty acids in the polar lipids of transgenic plants, reflecting the larger substrate pool available for acylation by enzymes of the Kennedy pathway. Expression of the O. tauri D6-desaturase in transgenic Camelina sativa plants also resulted in the accumulation of high levels of D6-desaturated fatty acids. This study provides evidence for the efficacy of using acyl-CoA-dependent D6-desaturases in the efficient metabolic engineering of transgenic plants with high value traits such as the synthesis of omega-3 LC-PUFAs.
Omega-3 (also called n-3) long-chain polyunsaturated fatty acids (≥C20; LC-PUFAs) are of consider... more Omega-3 (also called n-3) long-chain polyunsaturated fatty acids (≥C20; LC-PUFAs) are of considerable interest, based on clear evidence of dietary health benefits and the concurrent decline of global sources (fish oils). Generating alternative transgenic plant sources of omega-3 LC-PUFAs, i.e. eicosapentaenoic acid (20:5 n-3, EPA) and docosahexaenoic acid (22:6 n-3, DHA) has previously proved problematic. Here we describe a set of heterologous genes capable of efficiently directing synthesis of these fatty acids in the seed oil of the crop Camelina sativa, while simultaneously avoiding accumulation of undesirable intermediate fatty acids. We describe two iterations: RRes_EPA in which seeds contain EPA levels of up to 31% (mean 24%), and RRes_DHA, in which seeds accumulate up to 12% EPA and 14% DHA (mean 11% EPA and 8% DHA). These omega-3 LC-PUFA levels are equivalent to those in fish oils, and represent a sustainable, terrestrial source of these fatty acids. We also describe the distribution of these non-native fatty acids within C. sativa seed lipids, and consider these data in the context of our current understanding of acyl exchange during seed oil synthesis.
APA PsycNET Our Apologies! - The following features are not available with your current Browser c... more APA PsycNET Our Apologies! - The following features are not available with your current Browser configuration. - alerts user that their session is about to expire - display, print, save, export, and email selected records - get My ...
The synthesis and accumulation of long chain polyunsaturated fatty acids such as eicosapentaenoic... more The synthesis and accumulation of long chain polyunsaturated fatty acids such as eicosapentaenoic acid has previously been demonstrated in the seeds of transgenic plants. However, the obtained levels are relatively low, indicating the need for further studies and the better definition of the interplay between endogenous lipid synthesis and the nonnative transgene-encoded activities. In this study we have systematically compared three different transgenic configurations of the biosynthetic pathway for eicosapentaenoic acid, using lipidomic profiling to identify metabolic bottlenecks. We have also used genetic crossing to stack up to ten transgenes in Arabidopsis. These studies indicate several potential approaches to optimize the accumulation of target fatty acids in transgenic plants. Our data show the unexpected channeling of heterologous C20 polyunsaturated fatty acids into minor phospholipid species, and also the apparent negative metabolic regulation of phospholipid-dependent D6-desaturases. Collectively, this study confirms the benefits of iterative approaches to metabolic engineering of plant lipid synthesis.
Dietary omega-3 polyunsaturated fatty acids have a proven role in reducing the risk of cardiovasc... more Dietary omega-3 polyunsaturated fatty acids have a proven role in reducing the risk of cardiovascular disease and precursor disease states such as metabolic syndrome. Although most studies have focussed on the predominant omega-3 fatty acids found in fish oils (eicosapentaenoic acid and docosahexaenoic acid), recent evidence suggests similar health benefits from their common precursor, stearidonic acid. Stearidonic acid is a D6-unsaturated C18 omega-3 fatty acid present in a few plant species (mainly the Boraginaceae and Primulaceae) reflecting the general absence of D6-desaturation from higher plants. Using a D6-desaturase from Primula vialii, we generated transgenic Arabidopsis and linseed lines accumulating stearidonic acid in their seed lipids. Significantly, the P. vialii D6-desaturase specifically only utilises a-linolenic acid as a substrate, resulting in the accumulation of stearidonic acid but not omega-6 c-linolenic acid. Detailed lipid analysis revealed the accumulation of stearidonic acid in neutral lipids such as triacylglycerol but an absence from the acyl-CoA pool. In the case of linseed, the achieved levels of stearidonic acid (13.4% of triacylglycerols) are very similar to those found in the sole natural commercial plant source (Echium spp.) or transgenic soybean oil. However, both those latter oils contain c-linolenic acid, which is not normally present in fish oils and considered undesirable for heart-healthy applications. By contrast, the stearidonic acid-enriched linseed oil is essentially devoid of this fatty acid. Moreover, the overall omega-3 ⁄ omega-6 ratio for this modified linseed oil is also significantly higher. Thus, this nutritionally enhanced linseed oil may have superior health-beneficial properties. Burdge, 2006). By contrast, many such diets are now rich
This article will focus on the modification of plant seed oils to enhance their nutritional compo... more This article will focus on the modification of plant seed oils to enhance their nutritional composition. Such modifications will include C18 D6-desaturated fatty acids such as c-linolenic and stearidonic acid, omega-6 long-chain polyunsaturated fatty acids such as arachidonic acid, as well as the omega-3 long-chain polyunsaturated fatty acids (often named 'fish oils') such as eicosapentaenoic acid and docosahexaenoic acid. We will consider how new technologies (such as synthetic biology, next-generation sequencing and lipidomics) can help speed up and direct the development of desired traits in transgenic oilseeds. We will also discuss how manipulating triacylglycerol structure can further enhance the nutritional value of 'designer' oils. We will also consider how advances in model systems have translated into crops and the potential end-users for such novel oils (e.g. aquaculture, animal feed, human nutrition).
European Journal of Lipid Science and Technology, 2008
The fatty acid distributions of triacylglycerols (TAG) and major phospholipids (PL) obtained from... more The fatty acid distributions of triacylglycerols (TAG) and major phospholipids (PL) obtained from adzuki beans (Vigna angularis) were investigated. The total lipids extracted from the beans were separated by thin-layer chromatography (TLC) into eight fractions. The major lipid components were PL (63.5 wt-%), TAG (21.2 wt-%), steryl esters (7.5 wt-%) and hydrocarbons (5.1 wt-%), while free fatty acids, diacylglycerols (1,3-DAG and 1,2-DAG) and monoacylglycerols were also present in minor proportions (0.2-1.1 wt-%). The major PL components isolated from the beans were phosphatidylcholine (45.3 wt-%), phosphatidylethanolamine (25.8 wt-%) and phosphatidylinositol (21.5 wt-%). Phosphatidylinositol was unique in that it had the highest saturated fatty acid content among the three PL. With a few exceptions, however, the principal characteristics of the fatty acid distribution in the TAG and three PL were evident in the beans: Unsaturated fatty acids were predominantly concentrated in the sn-2 position while saturated fatty acids primary occupied the sn-1 or sn-3 position in the oils of the adzuki beans. In general, these results could be useful to both consumers and producers for the manufacture of traditional adzuki foods in Japan.
Non-vesicular lipid transfer at ER and plasma membrane (PM) contact sites (CS) is crucial for the... more Non-vesicular lipid transfer at ER and plasma membrane (PM) contact sites (CS) is crucial for the maintenance of membrane lipid homeostasis. Extended synaptotagmins (E-Syts) play a central role in this process as they act as molecular tethers of ER and PM and as lipid transfer proteins between these organelles. E-Syts are proteins constitutively anchored to the ER through an N-terminal hydrophobic segment and bind the PM via a variable number of C-terminal C2 domains. Synaptotagmins (SYTs) are the plant orthologous of E-Syts and regulate the ER–PM communication in response to abiotic stress. Combining different structural and biochemical techniques, we demonstrate that the binding of SYT1 to lipids occurs through a Ca2+-dependent lipid-binding site and by a site for phosphorylated forms of phosphatidylinositol, thus integrating two different molecular signals in response to stress. In addition, we show that SYT1 displays three highly flexible hinge points that provide conformational...
17th Euro Fed Lipid Congress 20-23 October 2019, Seville, SpainCastor plant produces seeds rich i... more 17th Euro Fed Lipid Congress 20-23 October 2019, Seville, SpainCastor plant produces seeds rich in ricinoleic acid (80 to 90%), an hydroxylated fatty acid, and with up to 60% oil. Castor seed oil has many non-food applications, including the production of biolubricants, bioplastics, cosmetics, paintings and covers. Moreover, castor plant is a productive oil crop that is not demanding in terms of soil and water and can be growth in marginal lands. However, the high toxicity of the seeds has always been an important burden at the time of manage large productions of this crop. Castor seed oil synthesis have been object of intensive research, due this plant is able to accumulate large amounts of one specific fatty acid, so the metabolic machinery associated to this fact is of a great interest because it can give information about how to make oil crops to accumulate single fatty acids. The research on castor seed biosynthetic machinery and biotechnology have been always hampered by the lack of a standard protocol of castor plant transformation. In this regard, in the present work we developed straightforward and reliable procedures enabling the transient and permanent transformation of castor plant. Transient transformation made possible to quick assessment of genetic constructions and testing different promoters in this species. Furthermore, permeant plants encoding for a silencing gene construct against castor hydroxylase were also developed. This plants produced seeds with lower levels of ricinoleic acid and a considerable reduction of the oil content. The comparison of this phenotype with the wild type plant and the OLE-1 high oleic castor seed mutant gave interesting insights of the process of castor seed oil synthesis. The perspectives of making castor seed an oil biofactory in the future will be discussed at the view of results
The authors acknowledge the support by the Plan Propio from University of Malaga, Campus de Excel... more The authors acknowledge the support by the Plan Propio from University of Malaga, Campus de Excelencia Internacional de Andalucia and by the Redes of Excelencia (BIO2014-56153-REDT) and BIO2017-82609-R & BIO2014-55380-R of the Ministerio de Economia, Industria y Competitividad
e21660Background: Alopecia is a common side effect of chemotherapy (CT) used in the treatment of ... more e21660Background: Alopecia is a common side effect of chemotherapy (CT) used in the treatment of breast cancer, which affects drastically patients’ quality of life. "Dignicap" is the first scalp co...
Wax esters (WEs) and steryl esters (SEs) are minor components of sunflower oils formed by the est... more Wax esters (WEs) and steryl esters (SEs) are minor components of sunflower oils formed by the esterification of long chain fatty alcohols and sterols to fatty acids. These compounds have similar carbon numbers and polarities making them difficult to separate using conventional chromatographic methods. In this study, electrospray ionisation-tandem mass spectrometry (ESI-MS/MS) allowed the rapid and accurate profiling of WEs and SEs acyl moieties in total ester fractions of common and mutant sunflower oils with different fatty acid profiles. The acyl composition of both WEs and SEs partially reflected that of the oil and the high oleic background displayed the lowest level of crystallisable waxes. ESI-MS/MS complemented by GC-MS analyses revealed that SEs contain 17-30% of previously unreported methylsterol moieties. We demonstrated that these compounds are overlooked by official sterol analytical methods which may have consequences for quality control and authentication of vegetable ...
The functional characterization of wax biosynthetic enzymes in transgenic plants has opened the p... more The functional characterization of wax biosynthetic enzymes in transgenic plants has opened the possibility of producing tailored wax esters (WEs) in the seeds of a suitable host crop. In this study, in addition to systematically evaluating a panel of WE biosynthetic activities, we have also modulated the acyl-CoA substrate pool, through the co-expression of acyl-ACP thioesterases, to direct the accumulation of medium-chain fatty acids. Using this combinatorial approach, we determined the additive contribution of both the varied acyl-CoA pool and biosynthetic enzyme substrate specificity to the accumulation of non-native WEs in the seeds of transgenic Camelina plants. A total of fourteen constructs were prepared containing selected FAR and WS genes in combination with an acyl-ACP thioesterase. All enzyme combinations led to the successful production of wax esters, of differing compositions. The impact of acyl-CoA thioesterase expression on wax ester accumulation varied depending on ...
Revista panamericana de salud publica = Pan American journal of public health, 2016
Objective To document the prevalence of patients on hemodialysis in southwestern Guatemala who ha... more Objective To document the prevalence of patients on hemodialysis in southwestern Guatemala who have chronic kidney disease (CKD) of non-traditional causes (CKDnt). Methods This cross-sectional descriptive study interviewed patients on hemodialysis at the Instituto Guatemalteco de Seguridad Social on their health and occupational history. Laboratory serum, urine and vital sign data at the initiation of hemodialysis were obtained from chart reviews. Patients were classified according to whether they had hypertension or obesity or neither. The proportion of patients with and without these traditional CKD risk factors was recorded and the association between demographic and occupational factors and a lack of traditional CKD risk factors analyzed using multivariate logistic regression. Results Of 242 total patients (including 171 non-diabetics) enrolled in hemodialysis in southwestern Guatemala, 45 (18.6% of total patients and 26.3% of non-diabetics) lacked traditional CKD risk factors. ...
Resumen basado en ficha elaborada por los autores o la responsable. Entre el material anexo se en... more Resumen basado en ficha elaborada por los autores o la responsable. Entre el material anexo se encuentran presentaciones de diapositivas, y otros elementos elaborados durante el desarrollo
Fish currently supplies only 40% of the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA... more Fish currently supplies only 40% of the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) required to allow all individuals globally to meet the minimum intake recommendation of 500 mg/d. Therefore, alternative sustainable sources are needed. The main objective was to investigate the ability of genetically engineered Camelina sativa (20% EPA) oil (CO) to enrich tissue EPA and DHA relative to an EPA-rich fish oil (FO) in mammals. Six-week-old male C57BL/6J mice were fed for 10 wk either a palm oil-containing control (C) diet or diets supplemented with EPA-CO or FO, with the C, low-EPA CO (COL), high-EPA CO (COH), low-EPA FO (FOL), and high-EPA FO (FOH) diets providing 0, 0.4, 3.4, 0.3, and 2.9 g EPA/kg diet, respectively. Liver, muscle, and brain were collected for fatty acid analysis, and blood glucose and serum lipids were quantified. The expression of selected hepatic genes involved in EPA and DHA biosynthesis and in modulating their cellular impact was determined. The oi...
A recombinant camelina plant or cell comprising one or more polynucleotides encoding a Δ6-desatur... more A recombinant camelina plant or cell comprising one or more polynucleotides encoding a Δ6-desaturase, a Δ6-elongase and a Δ5-desaturase operably linked with one or more regulatory sequences.
La función de daño es el parámetro fundamental del modelo de Nivel de Daño Económico (NDE). Los o... more La función de daño es el parámetro fundamental del modelo de Nivel de Daño Económico (NDE). Los objetivos fueron: evaluar los perjuicios de Armadillidium vulgare en el cultivo de girasol y determinar la función de daño en el cultivo para poder estimar el NDE. Las evaluaciones se realizaron en tres ciclos agrícolas según un diseño en bloques completos aleatorizados con cinco repeticiones. Se sembraron ocho semillas de girasol y se infestaron con: 0 (testigo), 20, 40, 60, 80 y 120 individuos m-2 de A. vulgare en parcelas de 1m 2. Se evaluaron los perjuicios en hipocótile y cotiledones, número de plantas m-2 y el rendimiento. Se calcularon las funciones de daño (regresión entre la densidad de A. vulgare y la proporción de pérdida de rendimiento). Se observaron diferencias en la proporción de plantas con perjuicios severos en el hipocótile entre las densidades de A. vulgare. Esta categoría de perjuicio se correlacionó con la densidad de A. vulgare, con el número de plantas m-2 y con el rendimiento. Las funciones de daño representaron una proporción de pérdida de rendimiento de 0,0033 (R 2 = 0,64), 0,0023 (R 2 = 0,49) y 0,0048 (R 2 = 0,71) por individuo por metro cuadrado para los tres ciclos agrícolas, respectivamente. Cuando se combinaron todos los datos ésta fue de 0,0034 (R 2 = 0,59). Considerando valores económicos promedio, los NDE de A. vulgare en el cultivo de girasol variaron entre 22 y 81 individuos m-2. Teniendo en cuenta los coeficientes de determinación y que A. vulgare tiene hábitos alimenticios variables, la función de daño de 0,0033 es recomendable en el cálculo de NDE de A. vulgare en girasol.
Omega-3 fatty acids are characterized by a double bond at the third carbon atom from the end of t... more Omega-3 fatty acids are characterized by a double bond at the third carbon atom from the end of the carbon chain. Latterly, long chain polyunsaturated omega-3 fatty acids such as eicosapentaenoic acid (EPA; 20:5Δ5,8,11,14,17) and docosahexanoic acid (DHA; 22:6 Δ4,7,10,13,16,19), which typically only enter the human diet via the consumption of oily fish, have attracted much attention. The health benefits of the omega-3 LC-PUFAs EPA and DHA are now well established. Given the desire for a sustainable supply of omega-LC-PUFA, efforts have focused on enhancing the composition of vegetable oils to include these important fatty acids. Specifically, EPA and DHA have been the focus of much study, with the ultimate goal of producing a terrestrial plant-based source of these so-called fish oils. Over the last decade, many genes encoding the primary LC-PUFA biosynthetic activities have been identified and characterized. This has allowed the reconstitution of the LC-PUFA biosynthetic pathway in...
Anexo I: Normativas regulatorias de los estatutos docentes de las provincias. Argentina, 2010. Pr... more Anexo I: Normativas regulatorias de los estatutos docentes de las provincias. Argentina, 2010. Provincias Estatuto del Docente vigente en la provincia Año última modificación Buenos Aires
The role of acyl-CoA-dependent D6-desaturation in the heterologous synthesis of omega-3 long-chai... more The role of acyl-CoA-dependent D6-desaturation in the heterologous synthesis of omega-3 long-chain polyunsaturated fatty acids was systematically evaluated in transgenic yeast and Arabidopsis thaliana. The acyl-CoA D6-desaturase from the picoalga Ostreococcus tauri and orthologous activities from mouse (Mus musculus) and salmon (Salmo salar) were shown to generate substantial levels of D6-desaturated acyl-CoAs, in contrast to the phospholipid-dependent D6desaturases from higher plants that failed to modify this metabolic pool. Transgenic plants expressing the acyl-CoA D6-desaturases from either O. tauri or salmon, in conjunction with the two additional activities required for the synthesis of C20 polyunsaturated fatty acids, contained higher levels of eicosapentaenoic acid compared with plants expressing the borage phospholipid-dependent D6-desaturase. The use of acyl-CoA-dependent D6-desaturases almost completely abolished the accumulation of unwanted biosynthetic intermediates such as c-linolenic acid in total seed lipids. Expression of acyl-CoA D6-desaturases resulted in increased distribution of long-chain polyunsaturated fatty acids in the polar lipids of transgenic plants, reflecting the larger substrate pool available for acylation by enzymes of the Kennedy pathway. Expression of the O. tauri D6-desaturase in transgenic Camelina sativa plants also resulted in the accumulation of high levels of D6-desaturated fatty acids. This study provides evidence for the efficacy of using acyl-CoA-dependent D6-desaturases in the efficient metabolic engineering of transgenic plants with high value traits such as the synthesis of omega-3 LC-PUFAs.
Omega-3 (also called n-3) long-chain polyunsaturated fatty acids (≥C20; LC-PUFAs) are of consider... more Omega-3 (also called n-3) long-chain polyunsaturated fatty acids (≥C20; LC-PUFAs) are of considerable interest, based on clear evidence of dietary health benefits and the concurrent decline of global sources (fish oils). Generating alternative transgenic plant sources of omega-3 LC-PUFAs, i.e. eicosapentaenoic acid (20:5 n-3, EPA) and docosahexaenoic acid (22:6 n-3, DHA) has previously proved problematic. Here we describe a set of heterologous genes capable of efficiently directing synthesis of these fatty acids in the seed oil of the crop Camelina sativa, while simultaneously avoiding accumulation of undesirable intermediate fatty acids. We describe two iterations: RRes_EPA in which seeds contain EPA levels of up to 31% (mean 24%), and RRes_DHA, in which seeds accumulate up to 12% EPA and 14% DHA (mean 11% EPA and 8% DHA). These omega-3 LC-PUFA levels are equivalent to those in fish oils, and represent a sustainable, terrestrial source of these fatty acids. We also describe the distribution of these non-native fatty acids within C. sativa seed lipids, and consider these data in the context of our current understanding of acyl exchange during seed oil synthesis.
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The synthesis and accumulation of long chain polyunsaturated fatty acids such as eicosapentaenoic... more The synthesis and accumulation of long chain polyunsaturated fatty acids such as eicosapentaenoic acid has previously been demonstrated in the seeds of transgenic plants. However, the obtained levels are relatively low, indicating the need for further studies and the better definition of the interplay between endogenous lipid synthesis and the nonnative transgene-encoded activities. In this study we have systematically compared three different transgenic configurations of the biosynthetic pathway for eicosapentaenoic acid, using lipidomic profiling to identify metabolic bottlenecks. We have also used genetic crossing to stack up to ten transgenes in Arabidopsis. These studies indicate several potential approaches to optimize the accumulation of target fatty acids in transgenic plants. Our data show the unexpected channeling of heterologous C20 polyunsaturated fatty acids into minor phospholipid species, and also the apparent negative metabolic regulation of phospholipid-dependent D6-desaturases. Collectively, this study confirms the benefits of iterative approaches to metabolic engineering of plant lipid synthesis.
Dietary omega-3 polyunsaturated fatty acids have a proven role in reducing the risk of cardiovasc... more Dietary omega-3 polyunsaturated fatty acids have a proven role in reducing the risk of cardiovascular disease and precursor disease states such as metabolic syndrome. Although most studies have focussed on the predominant omega-3 fatty acids found in fish oils (eicosapentaenoic acid and docosahexaenoic acid), recent evidence suggests similar health benefits from their common precursor, stearidonic acid. Stearidonic acid is a D6-unsaturated C18 omega-3 fatty acid present in a few plant species (mainly the Boraginaceae and Primulaceae) reflecting the general absence of D6-desaturation from higher plants. Using a D6-desaturase from Primula vialii, we generated transgenic Arabidopsis and linseed lines accumulating stearidonic acid in their seed lipids. Significantly, the P. vialii D6-desaturase specifically only utilises a-linolenic acid as a substrate, resulting in the accumulation of stearidonic acid but not omega-6 c-linolenic acid. Detailed lipid analysis revealed the accumulation of stearidonic acid in neutral lipids such as triacylglycerol but an absence from the acyl-CoA pool. In the case of linseed, the achieved levels of stearidonic acid (13.4% of triacylglycerols) are very similar to those found in the sole natural commercial plant source (Echium spp.) or transgenic soybean oil. However, both those latter oils contain c-linolenic acid, which is not normally present in fish oils and considered undesirable for heart-healthy applications. By contrast, the stearidonic acid-enriched linseed oil is essentially devoid of this fatty acid. Moreover, the overall omega-3 ⁄ omega-6 ratio for this modified linseed oil is also significantly higher. Thus, this nutritionally enhanced linseed oil may have superior health-beneficial properties. Burdge, 2006). By contrast, many such diets are now rich
This article will focus on the modification of plant seed oils to enhance their nutritional compo... more This article will focus on the modification of plant seed oils to enhance their nutritional composition. Such modifications will include C18 D6-desaturated fatty acids such as c-linolenic and stearidonic acid, omega-6 long-chain polyunsaturated fatty acids such as arachidonic acid, as well as the omega-3 long-chain polyunsaturated fatty acids (often named 'fish oils') such as eicosapentaenoic acid and docosahexaenoic acid. We will consider how new technologies (such as synthetic biology, next-generation sequencing and lipidomics) can help speed up and direct the development of desired traits in transgenic oilseeds. We will also discuss how manipulating triacylglycerol structure can further enhance the nutritional value of 'designer' oils. We will also consider how advances in model systems have translated into crops and the potential end-users for such novel oils (e.g. aquaculture, animal feed, human nutrition).
European Journal of Lipid Science and Technology, 2008
The fatty acid distributions of triacylglycerols (TAG) and major phospholipids (PL) obtained from... more The fatty acid distributions of triacylglycerols (TAG) and major phospholipids (PL) obtained from adzuki beans (Vigna angularis) were investigated. The total lipids extracted from the beans were separated by thin-layer chromatography (TLC) into eight fractions. The major lipid components were PL (63.5 wt-%), TAG (21.2 wt-%), steryl esters (7.5 wt-%) and hydrocarbons (5.1 wt-%), while free fatty acids, diacylglycerols (1,3-DAG and 1,2-DAG) and monoacylglycerols were also present in minor proportions (0.2-1.1 wt-%). The major PL components isolated from the beans were phosphatidylcholine (45.3 wt-%), phosphatidylethanolamine (25.8 wt-%) and phosphatidylinositol (21.5 wt-%). Phosphatidylinositol was unique in that it had the highest saturated fatty acid content among the three PL. With a few exceptions, however, the principal characteristics of the fatty acid distribution in the TAG and three PL were evident in the beans: Unsaturated fatty acids were predominantly concentrated in the sn-2 position while saturated fatty acids primary occupied the sn-1 or sn-3 position in the oils of the adzuki beans. In general, these results could be useful to both consumers and producers for the manufacture of traditional adzuki foods in Japan.
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