Analysis of triglyceride synthesis unveils a green algal soluble diacylglycerol acyltransferase and provides clues to potential enzymatic components of the chloroplast pathway

Background: Microalgal triglyceride (TAG) synthesis has attracted considerable attention. Particular emphasis has been put towards characterizing the algal homologs of the canonical rate-limiting enzymes, diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT). Less work has been done to analyze homologs from a phylogenetic perspective. In this work, we used HMMER iterative profiling and phylogenetic and functional analyses to determine the number and sequence characteristics of algal DGAT and PDAT, as well as related sequences that constitute their corresponding superfamilies. We included most algae with available genomes, as well as representative eukaryotic and prokaryotic species. Results: Amongst our main findings, we identified a novel clade of DGAT1-like proteins exclusive to red algae and glaucophyta and a previously uncharacterized subclade of DGAT2 proteins with an unusual number of transmembrane segments. Our analysis also revealed the existence of a novel DGAT exclusive to green algae with moderate similarity to plant soluble DGAT3. The DGAT3 clade shares a most recent ancestor with a group of uncharacterized proteins from cyanobacteria. Subcellular targeting prediction suggests that most green algal DGAT3 proteins are imported to the chloroplast, evidencing that the green algal chloroplast might have a soluble pathway for the de novo synthesis of TAGs. Heterologous expression of C. reinhardtii DGAT3 produces an increase in the accumulation of TAG, as evidenced by thin layer chromatography. Conclusions: Our analysis contributes to advance in the knowledge of complex superfamilies involved in lipid metabolism and provides clues to possible enzymatic players of chloroplast TAG synthesis.Instituto de Investigaciones Bioquímicas de La PlataFacultad de Ciencias Médica

Year-Round Forage Systems for Beef Cows and Calves

Beef cow systems in the USA are based on forages with little or no concentrates fed. Tall fescue (Festuca arundinacea Schreb. L.) is one of the important pasture forages in the lower Northeast and upper South (Allen et al., 2001). Limited research has been conducted on year-round all forage systems based on cool season forages. Stockpiling tall fescue in late summer-early fall provides good quality forage that is usually grazed rather than harvested. Forage systems including tall fescue and clover (Trifolium repens L.) produced excellent performance in beef cows and calves, with minimum inputs (Allen et al., 2001). The present experiment is a component of a larger initiative, Pasture-based Forage Systems for Appalachia. The specific objective of this experiment is to evaluate different forage systems for beef cows and calves

Development of a tomato pomace biorefinery based on a CO2-supercritical extraction process for the production of a high value lycopene product, bioenergy and digestate

Tomato peels and seeds (TP) are the most abundant canning industry waste actually used to produce biogas. TP is rich in lycopene (lyc) and represent a more sustainable feedstock than tomato fruits actually employed. It was therefore chosen as feedstock together with supercritical CO2 extraction (SFE-CO2) technology to develop a TP-SFE-CO2 biorefinery, topic scarcely investigated. Two TP were tested and although TP-SFE-CO2 parameters were the same, lyc recoveries depended by peel structure changes occurred during pre -SFE-CO2 drying step. Higher moisture (102.7 g kg-1 wet weight) permitted 97 % lyc recovery and gave a water-in-oil emulsion as extract. Mass balance confirmed that lyc isomerisation did not cause lyc losses. After a significant oil extraction, exhaust TP showed a biodegradability 64% higher than the raw one, attributable to fibre structure disruption. The biorefinery proposed (SFE_CO2+anaerobic digestion) determined positive economic revenue (+787.9 \u20ac t-1 TP) on the contrary of the actual TP management

Liver Transplantation Prevents Progressive Neurological Impairment in Argininemia

Argininemia is a rare hereditary disease due to a deficiency of hepatic arginase, which is the last enzyme of the urea cycle and hydrolyzes arginine to ornithine and urea. The onset of the disease is usually in childhood, and clinical manifestations include progressive spastic paraparesis and mental retardation. Liver involvement is less frequent and usually not as severe as observed in other UCDs. For this reason, and because usually there is a major neurological disease at diagnosis, patients with argininemia are rarely considered as candidates for OLT despite its capacity to replace the deficient enzyme by an active one. We report on long-term follow-up of two patients with argininemia. Patient 1 was diagnosed by the age of 20 months and despite appropriate conventional treatment progressed to spastic paraparesis with marked limp. OLT was performed at 10 years of age with normalization of plasmatic arginine levels and guanidino compounds. Ten years post-OLT, under free diet, there is no progression of neurological lesions. The second patient (previously reported by our group) was diagnosed at 2 months of age, during a neonatal cholestasis workup study. OLT was performed at the age of 7 years, due to liver cirrhosis with portal hypertension, in the absence of neurological lesions and an almost-normal brain MRI. After OLT, under free diet, there was normalization of plasmatic arginine levels and guanidino compounds. Twelve years post-OLT, she presents a normal neurological examination. We conclude that OLT prevents progressive neurological impairment in argininemia and should be considered when appropriate conventional treatment fails

Una calle nunca es una calle: el mundo de los frigoríficos

Repensando nuestra práctica docente, desde lo trabajado en el transcurso de la Especial Preparación correspondiente al área de Ciencias Sociales y en el Seminario: Patrimonio y Educación Preuniversitaria, es que nos propusimos la incorporación al Proyecto de Ciencias Sociales, como estudio de caso: los frigoríficos Swift y Armour. Se trata de un sitio histórico, una de las nominaciones a la lista patrimonial existente a nivel nacional, a escala de la microrregión del Gran La Plata; la calle Nueva York de Berisso. Corresponde al tipo Patrimonio Urbano Arquitectónico, como manifestación cultural tangible. En el proyecto institucional de la Escuela Graduada “J. V. González” se acordó trabajar el área de Ciencias Sociales, desde un eje estructurante “Organización política, económica y social de la Argentina y sus impactos territoriales a través del tiempo”, a partir del cual se desprenderían sub-ejes con contenidos propios para cada uno de los distintos grados que componen el ciclo.Trabajo perteneciente al Proyecto "Patrimonio y Educación" de la Prosecretaría de Asuntos AcadémicosPaper belonging to Project "Heritage and Education" of the Undersecretary for Academic AffairsTrabalho pertencente ao Projeto "Patrimônio e Educação"da Subsecretária da Assuntos AcadêmicosProsecretaría de Asuntos Académico

WHAT IS THE DIGESTATE?

As anaerobic digestion (AD) is quickly being harnessed in Italy and in other European countries, there is a need for a more in-depth description of the main by-product of the process, the digestate. Little information on digestate characteristics and composition is available and unclear legislation causes problems in biogas plant management. In this work, the organic matter (OM) of this matrix was described through chemical, biological, spectroscopic, and statistical approaches. It was shown that AD results in a strong reduction of the easily degradable fraction of the OM and an accumulation of recalcitrant molecules (possible humus precursors). This contributes to a relatively high biological stability of the residual OM content in the digestate and may lead to good amendment properties. Besides, the observed relative accumulation and the high mineralisation of nitrogen and phosphorus may point to the digestate as a readily available liquid fertiliser for agronomic use. Moreover, xenobiotics and pathogens respected limits for both biosolids and compost in Italian and European legislation

Inhibition of StearoylCoA Desaturase Activity Blocks Cell Cycle Progression and Induces Programmed Cell Death in Lung Cancer Cells

Lung cancer is the most frequent form of cancer. The survival rate for patients with metastatic lung cancer is ∼5%, hence alternative therapeutic strategies to treat this disease are critically needed. Recent studies suggest that lipid biosynthetic pathways, particularly fatty acid synthesis and desaturation, are promising molecular targets for cancer therapy. We have previously reported that inhibition of stearoylCoA desaturase-1 (SCD1), the enzyme that produces monounsaturated fatty acids (MUFA), impairs lung cancer cell proliferation, survival and invasiveness, and dramatically reduces tumor formation in mice. In this report, we show that inhibition of SCD activity in human lung cancer cells with the small molecule SCD inhibitor CVT-11127 reduced lipid synthesis and impaired proliferation by blocking the progression of cell cycle through the G1/S boundary and by triggering programmed cell death. These alterations resulting from SCD blockade were fully reversed by either oleic (18:1n-9), palmitoleic acid (16:1n-7) or cis-vaccenic acid (18:1n-7) demonstrating that cis-MUFA are key molecules for cancer cell proliferation. Additionally, co-treatment of cells with CVT-11127 and CP-640186, a specific acetylCoA carboxylase (ACC) inhibitor, did not potentiate the growth inhibitory effect of these compounds, suggesting that inhibition of ACC or SCD1 affects a similar target critical for cell proliferation, likely MUFA, the common fatty acid product in the pathway. This hypothesis was further reinforced by the observation that exogenous oleic acid reverses the anti-growth effect of SCD and ACC inhibitors. Finally, exogenous oleic acid restored the globally decreased levels of cell lipids in cells undergoing a blockade of SCD activity, indicating that active lipid synthesis is required for the fatty acid-mediated restoration of proliferation in SCD1-inhibited cells. Altogether, these observations suggest that SCD1 controls cell cycle progression and apoptosis and, consequently, the overall rate of proliferation in cancer cells through MUFA-mediated activation of lipid synthesis

ProteinWorldDB: querying radical pairwise alignments among protein sets from complete genomes

Motivation: Many analyses in modern biological research are based on comparisons between biological sequences, resulting in functional, evolutionary and structural inferences. When large numbers of sequences are compared, heuristics are often used resulting in a certain lack of accuracy. In order to improve and validate results of such comparisons, we have performed radical all-against-all comparisons of 4 million protein sequences belonging to the RefSeq database, using an implementation of the Smith–Waterman algorithm. This extremely intensive computational approach was made possible with the help of World Community Grid™, through the Genome Comparison Project. The resulting database, ProteinWorldDB, which contains coordinates of pairwise protein alignments and their respective scores, is now made available. Users can download, compare and analyze the results, filtered by genomes, protein functions or clusters. ProteinWorldDB is integrated with annotations derived from Swiss-Prot, Pfam, KEGG, NCBI Taxonomy database and gene ontology. The database is a unique and valuable asset, representing a major effort to create a reliable and consistent dataset of cross-comparisons of the whole protein content encoded in hundreds of completely sequenced genomes using a rigorous dynamic programming approach

Analysis of triglyceride synthesis unveils a green algal soluble diacylglycerol acyltransferase and provides clues to potential enzymatic components of the chloroplast pathway

Background: Microalgal triglyceride (TAG) synthesis has attracted considerable attention. Particular emphasis has been put towards characterizing the algal homologs of the canonical rate-limiting enzymes, diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT). Less work has been done to analyze homologs from a phylogenetic perspective. In this work, we used HMMER iterative profiling and phylogenetic and functional analyses to determine the number and sequence characteristics of algal DGAT and PDAT, as well as related sequences that constitute their corresponding superfamilies. We included most algae with available genomes, as well as representative eukaryotic and prokaryotic species. Results: Amongst our main findings, we identified a novel clade of DGAT1-like proteins exclusive to red algae and glaucophyta and a previously uncharacterized subclade of DGAT2 proteins with an unusual number of transmembrane segments. Our analysis also revealed the existence of a novel DGAT exclusive to green algae with moderate similarity to plant soluble DGAT3. The DGAT3 clade shares a most recent ancestor with a group of uncharacterized proteins from cyanobacteria. Subcellular targeting prediction suggests that most green algal DGAT3 proteins are imported to the chloroplast, evidencing that the green algal chloroplast might have a soluble pathway for the de novo synthesis of TAGs. Heterologous expression of C. reinhardtii DGAT3 produces an increase in the accumulation of TAG, as evidenced by thin layer chromatography. Conclusions: Our analysis contributes to advance in the knowledge of complex superfamilies involved in lipid metabolism and provides clues to possible enzymatic players of chloroplast TAG synthesis.Instituto de Investigaciones Bioquímicas de La PlataFacultad de Ciencias Médica

Chemical Characterization and Nematicidal Activity of the Essential Oil of Nepeta nuda L. ssp. pubescens and Nepeta curviflora Boiss. from Lebanon

The chemical characterization and the nematicidal activity of the essential oils from Nepeta nuda L. ssp. pubescens and Nepeta curviflora Boiss. growing wild in Lebanon are reported. A comparative study was carried out as, to the best of our knowledge, no information is available on Nepeta nuda L. ssp. pubescens. In addition, both Nepeta species were collected in the same geographical area in order to rule out the environmental factors influencing essential oil composition and bioactivity. The most abundant (> 5 %) components of N. nuda ssp. pubescens essential oil were pinene (12.89 %), 1-ethyl-1H-pyrrole (12.67 %), 1-cycloethyl- 1-(2-methylenecyclohexyl) ethanol (10.37 %), 3-methyl-2-cyclohexen-1-one (9.17 %) and 2,3-dimethyl-3- hexanol (5.88 %). Among oxygenated monoterpenes, two nepetalactones were identified, i.e. (E, Z)nepetalactone (2.24 %) and (Z, E)-nepetalactone (0.31 %). The major constituents (> 5 %) of N. curviflora essential oil were 2-isopropyl-5-methyl-3-cyclohexen-1-one (12.51%), (-)-spathulenol (11.73%), cis-Z-alpha-bisabolene epoxide (8.07 %), widdrol (7.0 %), (E, Z)-5,7-dodecadiene (6.93 %), dihydronepetalactone (5.57 %) and 4-propyl-cyclohexene (5.43 %). The essential oil of N. curviflora was more active than the N. nuda ssp. pubescens one against the nematode Panagrolaimus rigidus. According to the motility assay, LD50 was 0.5 mg/mL and 2.5 mg/mL 24 h after treatment with N. curviflora and N. nuda ssp. pubescens essential oil, respectively