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A novel bacterial strain, designated SGD-1123T was isolated from Chorao Island, in Goa Province, India. The strain was found to be able to grow at 15–42 °C, pH 5–12 and 0–12 % (w/v) NaCl. The whole cell hydrolysates were found to contain meso-diaminopimelic acid, galactose and arabinose. The major fatty acids were identified as iso-C15:0 and anteiso-C15:0, MK-7 was identified as the predominant menaquinone and the predominant polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified aminolipid. The genomic DNA G+C content was determined to be 44.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences placed the isolate within the genus Bacillus and further revealed that strain SGD-1123T had highest sequence similarity with Bacillus aquimaris, and forms a separate clade with its closest relatives i.e. B. aquimaris, Bacillus vietnamensis and Bacillus marisflavi, with which it shares 94.5, 94.1 and 94.1 % similarity respectively. The phylogenetic, chemotaxonomic and phenotypic analyses indicated that strain SGD-1123T represents a novel species within the genus Bacillus, for which the name Bacillus enclensis is proposed. The type strain is SGD-1123T (NCIM 5450T=CCTCC AB 2011125T).  相似文献   
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Liquid mixing scale-up in pharmaceutical industry has often been based on empirical approach in spite of tremendous understanding of liquid mixing scale-up in engineering fields. In this work, we attempt to provide a model-based approach to scale-up dissolution process from a 2 l lab-scale vessel to a 4,000 l scale vessel used in manufacturing. Propylparaben was used as a model compound to verify the model predictions for operating conditions at commercial scale that would result in similar dissolution profile as observed in lab scale. Geometric similarity was maintained between both of the scales to ensure similar mixing characteristics. We utilized computational fluid dynamics (CFD) to ensure that the operating conditions at laboratory and commercial scale will result in similar power per unit volume (P/V). Utilizing this simple scale-up criterion of similar P/V across different scales, results obtained indicate fairly good reproducibility of the dissolution profiles between the two scales. Utilization of concepts of design of experiments enabled summarizing scale-up results in statistically meaningful parameters, for example −90% dissolution in lab scale at a given time under certain operating conditions will result in 75–88% at commercial scale with 95% confidence interval when P/V is maintained constant across the two scales. In this work, we have successfully demonstrated that scale-up of solid dissolution can be done using a systematic process of lab-scale experiments followed by simple CFD modeling to predict commercial-scale experimental conditions.  相似文献   
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International Microbiology - Indian lotus (Nelumbo nucifera) is one of the dominant aquatic plants cultivated in Dal Lake, situated at 1586 m above mean sea level (MSL) in the northeast of...  相似文献   
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Available evidence from a multitude of studies on the effects of 4-hydroxynonenal (HNE) on cellular processes seem to converge on some common themes: (i) concentration-dependent opposing effects of HNE on key signaling components (e.g. protein kinase C, adenylate cyclase) predict that certain constitutive levels of HNE may be needed for normal cell functions - lowering of this constitutive HNE level in cells promotes proliferative machinery while an increase in this level promotes apoptotic signaling; (ii) HNE is a common denominator in stress-induced apoptosis caused by H(2)O(2), superoxide, UV, heat or oxidant chemicals such as doxorubicin; and (iii) HNE can modulate ligand-independent signaling by membrane receptors such as EGFR or Fas (CD95) and may act as a sensor of external stimuli for eliciting stress-response. Against a backdrop of various reported effects of HNE, in vitro and in vivo, we have critically evaluated the above mentioned hypotheses suggesting a key role of HNE in signaling.  相似文献   
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An increase in cell number is one of the most prominent characteristics of cancer cells. This may be caused by an increase in cell proliferation or decrease in cell death. Queuine is one of the modified base which is found at first anticodon position of specific tRNAs. It is ubiquitously present throughout the living system except mycoplasma and yeast. The tRNAs of Q-family are completely modified to Q-tRNAs in terminally differentiated somatic cells, however hypomodification of Q-tRNA is closely associated with cell proliferation and malignancy. Queuine participates at various cellular functions such as regulation of cell proliferation, cell signaling and alteration in the expression of growth associated proto-oncogenes. Like other proto-oncogenes bcl2 is known to involve in cell survival by inhibiting apoptosis. Queuine or Q-tRNA is suggested to inhibit cell proliferation but the mechanism of regulation of cell proliferation by queuine or Q-tRNA is not well understood. Therefore, in the present study regulation in cell proliferation by queuine in vivo and in vitro as well as the expression of cell death regulatory protein Bcl2 are investigated. For this DLAT cancerous mouse, U87 cell line and HepG2 cell line are treated with different concentrations of queuine and the effect of queuine on cell proliferation and apoptosis are studied. The results indicate that queuine down regulates cell proliferation and expression of Bcl2 protein, suggesting that queuine promotes cell death and participates in the regulation of cell proliferation.  相似文献   
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Karpe YA  Aher PP  Lole KS 《PloS one》2011,6(7):e22336
Chikungunya virus (CHIKV) is an insect borne virus (genus: Alphavirus) which causes acute febrile illness in humans followed by a prolonged arthralgic disease that affects the joints of the extremities. Re-emergence of the virus in the form of outbreaks in last 6-7 years has posed a serious public health problem. CHIKV has a positive sense single stranded RNA genome of about 12,000 nt. Open reading frame 1 of the viral genome encodes a polyprotein precursor, nsP1234, which is processed further into different non structural proteins (nsP1, nsP2, nsP3 and nsP4). Sequence based analyses have shown helicase domain at the N-terminus and protease domain at C-terminus of nsP2. A detailed biochemical analysis of NTPase/RNA helicase and 5'-RNA phosphatase activities of recombinant CHIKV-nsP2T protein (containing conserved NTPase/helicase motifs in the N-terminus and partial papain like protease domain at the C-terminus) was carried out. The protein could hydrolyze all NTPs except dTTP and showed better efficiency for ATP, dATP, GTP and dGTP hydrolysis. ATP was the most preferred substrate by the enzyme. CHIKV-nsP2T also showed 5'-triphosphatase (RTPase) activity that specifically removes the γ-phosphate from the 5' end of RNA. Both NTPase and RTPase activities of the protein were completely dependent on Mg(2+) ions. RTPase activity was inhibited by ATP showing sharing of the binding motif by NTP and RNA. Both enzymatic activities were drastically reduced by mutations in the NTP binding motif (GKT) and co-factor, Mg(2+) ion binding motif (DEXX) suggesting that they have a common catalytic site.  相似文献   
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