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Summary Plotting intracellular ATP concentrations as a function of time during cellulase production byTrichoderma reesei, provides a good evaluation of fungal growth and specific rate of cellulose consumption. ATP content evaluation is of great help for running fed-batch and semi-continuous fermentations.  相似文献   
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Bioconversion of acetic acid to methane by a crude culture of methanogens in a continuous multireactor system was investigated. Culture of methanogens was drawn from an active cow-dung digester (12 days) and was grown in a semisynthetic medium (pH 6.3, 37 degrees C) with acetic acid as the sole carbon source. The solubilities of CO(2), HCO(3) (-), and CO(3) (2-) increased with the rise in pH and exercised considerable influence on the gas composition. Various mechanisms for methanogenesis of acetic acid based on the available pathways were considered. Experimental data were compared with these mechanisms, the best fit was determined, and the corresponding rate expression was identified. This mechanism predicted that, of the total methane produced, 72%;comes from acetic acid directly and 28%;via the CO(2) reduction route.  相似文献   
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A simple differential method based on measurement of an intracellular pigment of Aspergillus wentii was developed for estimation of the individual growths of two fungi, Trichoderma reesei and A. wentii, in mixed-culture fermentation of an insoluble cellulosic substrate.  相似文献   
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Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disorder wherein the contributory role of oxidative stress has been established in the synovial fluid. As availability of synovial fluid is limited, this study aimed to evaluate in the peripheral blood of patients with RA, the relationship if any, between the extent of oxidative stress in terms of generation of reactive oxygen species (ROS) in neutrophils, plasma NADPH oxidase and myeloperoxidase activity with markers of oxidative damage, circulating cytokines and disease activity score (DAS28). In patients with RA, neutrophils in peripheral blood demonstrated an enhanced generation of ROS, coupled with depletion of free radical scavenging activity. Furthermore, the NADPH oxidase and myeloperoxidase activity was enhanced as were markers of damage. There was a positive correlation between the DAS 28 and generation of ROS, NADPH oxidase and myeloperoxidase activity as also with oxidative stress mediated protein carbonylation. Patients with RA demonstrated an increase in proinflammatory (IL-17, IL-23, and IFN-γ) and some anti-inflammatory (IL-4, IL-5, and TGF-β) cytokines. Although the levels of IL-17 correlated positively with generation of ROS, myeloperoxidase, markers of protein damage and DAS28, IL-23 correlated positively only with protein damage, and negatively with free radical scavenging activity. Importantly, incubation of neutrophils from healthy donors with plasma or SF from patients with RA translated into an enhanced generation of ROS, along with an elevation of intracellular proinflammatory cytokines. Taken together, in patients with RA, circulating neutrophils mediated a shift in the oxidant/antioxidant balance favouring the former, which translated into protein damage and contributed towards disease progression.  相似文献   
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Background  

Selenocysteine (Sec) is a selenium-containing amino acid that is co-translationally inserted into nascent polypeptides by recoding UGA codons. Selenoproteins occur in both eukaryotes and prokaryotes, but the selenoprotein content of organisms (selenoproteome) is highly variable and some organisms do not utilize Sec at all.  相似文献   
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Plants have to cope with changing seasons and adverse environmental conditions. Being sessile, plants have developed elaborate mechanisms for their survival that allow them to sense and adapt to the environment and reproduce successfully. A major adaptive trait for the survival of trees of temperate and boreal forests is the induction of growth cessation in anticipation of winters. In the last few years enormous progress has been made to elucidate the molecular mechanisms underlying SDs induced growth cessation in model perennial tree hybrid aspen (Populus tremula × P. tremuloides). In this review we discuss the molecular mechanism underlying photoperiodic control of growth cessation and adaptive responses.  相似文献   
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