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Journal of Plant Biochemistry and Biotechnology - Vitamin E deficiency is a serious health concern in humans. Biofortification of maize kernel with high vitamin E (α-tocopherol) provides...  相似文献   
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In these studies, butanol (acetone butanol ethanol or ABE) was produced from wheat straw hydrolysate (WSH) in batch cultures using Clostridium beijerinckii P260. In control fermentation 48.9 g L−1 glucose (initial sugar 62.0 g L−1) was used to produce 20.1 g L−1 ABE with a productivity and yield of 0.28 g L−1 h−1 and 0.41, respectively. In a similar experiment where WSH (60.2 g L−1 total sugars obtained from hydrolysis of 86 g L−1 wheat straw) was used, the culture produced 25.0 g L−1 ABE with a productivity and yield of 0.60 g L−1 h−1 and 0.42, respectively. These results are superior to the control experiment and productivity was improved by 214%. When WSH was supplemented with 35 g L−1 glucose, a reactor productivity was improved to 0.63 g L−1 h−1 with a yield of 0.42. In this case, ABE concentration in the broth was 28.2 g L−1. When WSH was supplemented with 60 g L−1 glucose, the resultant medium containing 128.3 g L−1 sugars was successfully fermented (due to product removal) to produce 47.6 g L−1 ABE, and the culture utilized all the sugars (glucose, xylose, arabinose, galactose, and mannose). These results demonstrate that C. beijerinckii P260 has excellent capacity to convert biomass derived sugars to solvents and can produce over 28 g L−1 (in one case 41.7 g L−1 from glucose) ABE from WSH. Medium containing 250 g L−1 glucose resulted in no growth and no ABE production. Mixtures containing WSH + 140 g L−1 glucose (total sugar approximately 200 g L−1) showed poor growth and poor ABE production. Mention of trade names or commercial products in this article is solely for the purpose of providing scientific information and does not imply recommendation or endorsement by the United States Department of Agriculture.  相似文献   
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Deep terrestrial subsurface represents a huge repository of global prokaryotic biomass. Given its vastness and importance, microbial life within the deep subsurface continental crust remains under-represented in global studies. We characterize the microbial communities of deep, extreme and oligotrophic realm hosted by crystalline Archaean granitic rocks underneath the Deccan Traps, through sampling via 3000 m deep scientific borehole at Koyna, India through metagenomics, amplicon sequencing and cultivation-based analyses. Gene sequences 16S rRNA (7.37 × 106) show considerable bacterial diversity and the existence of a core microbiome (5724 operational taxonomic units conserved out of a total 118,064 OTUs) across the depths. Relative abundance of different taxa of core microbiome varies with depth in response to prevailing lithology and geochemistry. Co-occurrence network analysis and cultivation attempt to elucidate close interactions among autotrophic and organotrophic bacteria. Shotgun metagenomics reveals a major role of autotrophic carbon fixation via the Wood–Ljungdahl pathway and genes responsible for energy and carbon metabolism. Deeper analysis suggests the existence of an ‘acetate switch’, coordinating biosynthesis and cellular homeostasis. We conclude that the microbial life in the nutrient- and energy-limited deep granitic crust is constrained by the depth and managed by a few core members via a close interplay between autotrophy and organotrophy.  相似文献   
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Microtubule associated tumor suppressor 1 (MTUS1) has been recognized as a tumor suppressor gene in multiple cancers. However, the molecular mechanisms underlying the regulation of MTUS1 are yet to be investigated. This study aimed to clarify the significance of DNA methylation in silencing MTUS1 expression. We report that MTUS1 acts as tumor suppressor in non-small cell lung carcinoma (NSCLC). Analysis of in silico database and subsequent knockdown of DNMT1 suggested an inverse correlation between DNMT1 and MTUS1 function. Interestingly, increased methylation at MTUS1 promoter is associated with low expression of MTUS1. Treatment with DNA methyltransferases (DNMTs) inhibitor, 5-aza-2′-deoxycytidine (AZA) leads to both reduced promoter methylation accompanied with enrichment of H3K9Ac and enhanced MTUS1 expression. Remarkably, knockdown of MTUS1 showed increased proliferation and migration of NSCLC cells in contrast to diminished proliferation and migration, upon treatment with AZA. We concluded that low expression of MTUS1 correlates to DNA methylation and histone deacetylation in human NSCLC.  相似文献   
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A total of 292 randomly selected subjects belonging to two indigenous Arab tribes (Harbi and Ghamid) and two immigrant tribes (Mograbi and Mowallad), residents in Western Saudi Arabia, have been tested for genetic variants of six blood groups, four serum proteins, and five red cell enzyme systems. The distribution of the polymorphic systems was different between indigenous and immigrant tribes, and the present Arab population shows a considerable degree of admixture from the surrounding countries, in particular Africa.  相似文献   
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Macrophomina phaseolina, the well-known jute pathogenic fungus produces very low levels of both extra- and intracellular carboxymethylcellulase even in the absence of any cellulose as carbon source in the medium. However, the production of these enzymes is greatly induced by soluble carboxymethylcellulose. The carboxymethylcellulase inM.phaseolina is repressed by glucose.  相似文献   
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