PROSPECTS OF VEGETABLE OIL DERIVATIVES FOR RURAL AGRICULTURAL ENERGY IN INDIA

Svijet je suočen s dvojnom krizom: krizom nestajanja fosilnih goriva i krizom degradacije okoliša. Alternativna goriva, očuvanje i upravljanje energijom, energetska učinkovitost i zaštita okoliša posljednjih su godina dobili na značenju. Kao alternativa dizel gorivu dosta obećavaju esterificirana biljna ulja koja su ekološki vrlo pogodna. U ruralnoj Indiji potreba za naftom otpada na poljoprivrednu mehanizaciju poput traktora i vršilica. Poljoprivrednici koji posjeduju marginalna i velika zemljišta mogu ispuniti zahtjeve dizel goriva tako da siju uljarice na vlastitoj zemlji. U ovom radu procjenjuje se isplativost lokalne proizvodnje biljnih ulja u jednom malom oglednom selu u središnjoj Indiji. Analiziraju se metilni esteri masnih kiselina iz ulja pamukovog sjemena, sojinog ulja, ulja balanitesa i jatrofina ulja da bi se ustanovila njihova svojstva i radni učinak u dizel motoru, a procjenjuje se i potrebna površina zemljišta za uzgoj tih uljnih kultura kako bi se udovoljilo potrebama seoske poljoprivrede za gorivom. Rezultati pokazuju da kalorična vrijednost metilnih estera iznosi dizela, a i druga su svojstva posve usporediva s dizelom. Analiza radnog učinka metilnih estera u motoru pokazuje neznatno smanjenje toplinske učinkovitosti od oko , dok su emisije smanjene za do u usporedbi s dizelom. Izvršena je i ekonomska analiza te je ustanovljeno da je korištenje derivata biljnih ulja kao zamjene za dizel gorivo skuplje od korištenja mineralnog dizela.The world is confronting the twin crises of fossil fuel depletion and environmental degradation. Alternative fuels, energy conservation and management, energy efficiency and environmental protection have become increasingly import in recent years. Among alternative fuels, esterified vegetable oils hold good promise as eco-friendly alternatives to diesel fuel. In rural India, of the petroleum diesel requirement is for agricultural equipment such as tractors and threshers. Marginal farmers and large landholders can meet their diesel requirement by sowing oil yielding crops on their own lands. This paper evaluates the feasibility of the local production of vegetable oil for a small representative village in central India. Fatty acid methyl esters of cottonseed oil, soybean oil, balanites oil and jatropha oil were analyzed for their properties and performance in diesel engines. The land required to grow these oil crops in order to meet rural agricultural diesel requirements was estimated. The results indicate that the calorific value of these methyl esters is that of diesel and the other properties are quite comparable with diesel. Engine performance analysis of these methyl esters indicates that there is a slight decrease in thermal efficiency of approximately , while emissions are reduced by to as compared to diesel. Economic analysis was also performed and it was found that vegetable oil derivatives as diesel fuel substitutes are costlier than mineral diesel

Integrin β3 Crosstalk with VEGFR Accommodating Tyrosine Phosphorylation as a Regulatory Switch

Integrins mediate cell adhesion, migration, and survival by connecting intracellular machinery with the surrounding extracellular matrix. Previous studies demonstrated the importance of the interaction between β3 integrin and VEGF type 2 receptor (VEGFR2) in VEGF-induced angiogenesis. Here we present in vitro evidence of the direct association between the cytoplasmic tails (CTs) of β3 and VEGFR2. Specifically, the membrane-proximal motif around 801YLSI in VEGFR2 mediates its binding to non-phosphorylated β3CT, accommodating an α-helical turn in integrin bound conformation. We also show that Y747 phosphorylation of β3 enhances the above interaction. To demonstrate the importance of β3 phosphorylation in endothelial cell functions, we synthesized β3CT-mimicking Y747 phosphorylated and unphosphorylated membrane permeable peptides. We show that a peptide containing phospho-Y747 but not F747 significantly inhibits VEGF-induced signaling and angiogenesis. Moreover, phospho-Y747 peptide exhibits inhibitory effect only in WT but not in β3 integrin knock-out or β3 integrin knock-in cells expressing β3 with two tyrosines substituted for phenylalanines, demonstrating its specificity. Importantly, these peptides have no effect on fibroblast growth factor receptor signaling. Collectively these data provide novel mechanistic insights into phosphorylation dependent cross-talk between integrin and VEGFR2

Fermentation, Isolation, Structure, and antidiabetic activity of NFAT-133 produced by Streptomyces strain PM0324667

Type-2 diabetes is mediated by defects in either insulin secretion or insulin action. In an effort to identify extracts that may stimulate glucose uptake, similar to insulin, a high throughput-screening assay for measuring glucose uptake in skeletal muscle cells was established. During the screening studies to discover novel antidiabetic compounds from microbial resources a Streptomyces strain PM0324667 (MTCC 5543, the Strain accession number at Institute of Microbial Technology, Chandigarh, India), an isolate from arid soil was identified which expressed a secondary metabolite that induced glucose uptake in L6 skeletal muscle cells. By employing bioactivity guided fractionation techniques, a tri-substituted simple aromatic compound with anti-diabetic potential was isolated. It was characterized based on MS and 2D NMR spectral data and identified as NFAT-133 which is a known immunosuppressive agent that inhibits NFAT-dependent transcription in vitro. Our investigations revealed the antidiabetic potential of NFAT-133. The compound induced glucose uptake in differentiated L6 myotubes with an EC50 of 6.3 ± 1.8 μM without activating the peroxisome proliferator-activated receptor-γ. Further, NFAT-133 was also efficacious in vivo in diabetic animals and reduced systemic glucose levels. Thus it is a potential lead compound which can be considered for development as a therapeutic for the treatment of type-2 diabetes. We have reported herewith the isolation of the producer microbe, fermentation, purification, in vitro, and in vivo antidiabetic activity of the compound

Integrin,alphaIIbbeta3: Tale of Two Cytoplasmic Tails

Metazoans\u27 cells adapt continuously in order to survive in a highly dynamic extracellular environment which requires a flow of information from extracellular matrix (ECM) to the cytoplasm. This process is controlled by integrins, the heterodimeric (α, β), glycoprotein adhesion receptors, which mediate cell-cell and cell-ECM interactions. The unique bidirectional flow of information through integrins involves ‘inside-out’ signals that allow them to interact with extracellular ligands, and ligand-dependent ‘outside-in’ signals that adjust the cellular response to cell adhesion. These integrins-ECM interactions are controlled by integrins\u27 extracellular domains whereas integrins-cytoplasmic proteins interactions are controlled via their cytoplasmic tails (CTs). ^ This thesis focuses on the CTs of platelet integrin αllbβ 3 and their interaction with two different adapter proteins, skelemin and Shc. Phosphorylation of the integrin tails is considered to be one of the spatiotemporal, regulatory mechanisms. In case of β3CT, phosphorylation of the two tyrosine residues (747pY, 759pY) is crucial for controlling its function. Chapters 4 and 5 of this thesis deal with structural investigations of tyrosine phosphorylation of β3CT and its impact on the cross-talk with vascular endothelium growth factor receptor 2 (VEGFR2). ^ Chapter 6 concentrates on interaction between bi-phosphorylated β 3CT (747pY, 759pY) and an adaptor protein, Shc. Previous studies have shown that by specifically recognizing the tyrosine phosphorylated integrin β3, Shc mediates integrin ‘ outside-in’ signaling, although the structural basis of this interaction has remained nebulous. In chapter 6, we present the detailed structural analysis of Shc Phosphotyrosine Binding (PTB) domain in complex with the bi-phosphorylated β 3CT which reveals the first snapshot of an integrin cytoplasmic tail bound to a target for mediating the ‘outside-in’ signaling. ^ Finally, in Chapter 7, we decipher the interaction between CTs of α llbβ3 with a scaffold protein, skelemin. The two-tandem immunoglobulin C2-like repeats of skelemin (SklgC4, SklgC5, and SklgC45 when together) have been shown to interact with integrin β3CT. Our data shows that SklgC45 domains form a complex not only with integrin β 3CT but also, surprisingly, with the αllbCT. These data provide the first molecular insights into how skelemin may interact with integrins and regulate integrin-mediated signaling and cell spreading.

Mechanistic roles of tyrosine phosphorylation in reversible amyloids, autoinhibition, and endosomal membrane association of ALIX

Human apoptosis-linked gene-2 interacting protein X (ALIX), a versatile adapter protein, regulates essential cellular processes by shuttling between late endosomal membranes and the cytosol, determined by its interactions with Src kinase. Here, we investigate the molecular basis of these transitions and the effects of tyrosine phosphorylation on the interplay between structure, assembly, and intramolecular and intermolecular interactions of ALIX. As evidenced by transmission electron microscopy, fluorescence and circular dichroism spectroscopy, the proline-rich domain of ALIX, which encodes binding epitopes of multiple cellular partners, formed rope-like β-sheet-rich reversible amyloid fibrils that dissolved upon Src-mediated phosphorylation and were restored on protein-tyrosine phosphatase 1B-mediated dephosphorylation of its conserved tyrosine residues. Analyses of the Bro1 domain of ALIX by solution NMR spectroscopy elucidated the conformational changes originating from its phosphorylation by Src and established that Bro1 binds to hyperphosphorylated proline-rich domain and to analogs of late endosomal membranes via its highly basic surface. These results uncover the autoinhibition mechanism that relocates ALIX to the cytosol and the diverse roles played by tyrosine phosphorylation in cellular and membrane functions of ALIX

Avidity-Based Method for the Efficient Generation of Monoubiquitinated Recombinant Proteins

Monoubiquitination of proteins governs diverse physiological processes, and its dysregulation is implicated in multiple pathologies. The difficulty of preparing sufficient material often complicates the biophysical studies of monoubiquitinated recombinant proteins. Here we describe a robust avidity-based method that overcomes this problem. As a proof-of-concept, we produced milligram quantities of two monoubiquitinated targets, Parkinson's protein α-synuclein and ESCRT-protein ALIX, using NEDD4-family E3 ligases. Monoubiquitination hotspots were identified by quantitative chemical proteomics. Using FRAP and dye-binding assays, we uncovered strikingly opposite effects of monoubiquitination on the phase separation and fibrillization properties of these two amyloidogenic proteins, reflecting differences in their intermolecular interactions, thereby providing unique insights into the impact of monoubiquitination on protein aggregation