Probing the endosperm gene expression landscape in Brassica napus

<p>Abstract</p> <p>Background</p> <p>In species with exalbuminous seeds, the endosperm is eventually consumed and its space occupied by the embryo during seed development. However, the main constituent of the early developing seed is the liquid endosperm, and a significant portion of the carbon resources for the ensuing stages of seed development arrive at the embryo through the endosperm. In contrast to the extensive study of species with persistent endosperm, little is known about the global gene expression pattern in the endosperm of exalbuminous seed species such as crucifer oilseeds.</p> <p>Results</p> <p>We took a multiparallel approach that combines ESTs, protein profiling and microarray analyses to look into the gene expression landscape in the endosperm of the oilseed crop <it>Brassica napus</it>. An EST collection of over 30,000 entries allowed us to detect close to 10,000 unisequences expressed in the endosperm. A protein profile analysis of more than 800 proteins corroborated several signature pathways uncovered by abundant ESTs. Using microarray analyses, we identified genes that are differentially or highly expressed across all developmental stages. These complementary analyses provided insight on several prominent metabolic pathways in the endosperm. We also discovered that a transcription factor <it>LEAFY COTYLEDON </it>(<it>LEC1</it>) was highly expressed in the endosperm and that the regulatory cascade downstream of <it>LEC1 </it>operates in the endosperm.</p> <p>Conclusion</p> <p>The endosperm EST collection and the microarray dataset provide a basic genomic resource for dissecting metabolic and developmental events important for oilseed improvement. Our findings on the featured metabolic processes and the <it>LEC1 </it>regulatory cascade offer new angles for investigation on the integration of endosperm gene expression with embryo development and storage product deposition in seed development.</p

Molecular characterization and antibacterial effect of endophytic actinomycetes Nocardiopsis sp. GRG1 (KT235640) from brown algae against MDR strains of uropathogens

Our study is to evaluate the potential bioactive compound of Nocardiopsis sp. GRG1 (KT235640) and its antibacterial activity against multi drug resistant strains (MDRS) on urinary tract infections (UTIs). Two brown algae samples were collected and were subjected to isolation of endophytic actinomycetes. 100 strains of actinomycetes were isolated from algal samples based on observation of morphology and physiological characters. 40 strains were active in antagonistic activity against various clinical pathogens. Among the strains, 10 showed better antimicrobial activity against MDRS on UTIs. The secondary metabolite of Nocardiopsis sp. GRG1 (KT235640) has showed tremendous antibacterial activity against UTI pathogens compared to other strains. Influence of various growth parameters were used for synthesis of secondary metabolites, such as optimum pH 7, incubation time 5–7 days, temperature (30 °C), salinity (5%), fructose and mannitol as the suitable carbon and nitrogen sources. At 100 μg/ml concentration MIC of Nocardiopsis sp. GRG1 (KT235640) showed highest percentage of inhibition against Proteus mirabilis (85%), and E.coli, Staphylococcus auerues, Psuedomonas aeroginasa, Enterobactor sp and Coagulinase negative staphylococci 78–85% respectively

Experimental and numerical investigation on suppression of thermal stratification in a water-pool: PIV measurements and CFD simulations

This paper deals with experimental and numerical investigation on thermal stratification phenomenon conducted in a scaled transparent pool using Particle Image Velocimetry (PIV) technique and Computational Fluid Dynamics (CFD) simulations respectively. Experiments were designed to simulate thermal stratification in a pool with an immersed heat exchanger. In general, pools with an immersed heat exchanger tend to get thermally stratified; preventing mixing and participation of the whole pool during the heat removal process. The study presented in the paper, focuses on quantification of thermal stratification in the pool without shrouds and examines the effect of shrouds on suppression of thermal stratification. The installation of three shrouds divides the pool in four compartments and ensures participation of the whole pool inventory in the heat removal process. In all the four compartments, pool water circulation was observed since the beginning of the heat transfer from the heater. In a three-shroud configuration, because of mixing, rate of rise of temperature of water near the top decreases