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31.
Tyndall JD Sinchaikul S Fothergill-Gilmore LA Taylor P Walkinshaw MD 《Journal of molecular biology》2002,323(5):859-869
We describe the first lipase structure from a thermophilic organism. It shares less than 20% amino acid sequence identity with other lipases for which there are crystal structures, and shows significant insertions compared with the typical alpha/beta hydrolase canonical fold. The structure contains a zinc-binding site which is unique among all lipases with known structures, and which may play a role in enhancing thermal stability. Zinc binding is mediated by two histidine and two aspartic acid residues. These residues are present in comparable positions in the sequences of certain lipases for which there is as yet no crystal structural information, such as those from Staphylococcal species and Arabidopsis thaliana. The structure of Bacillus stearothermophilus P1 lipase provides a template for other thermostable lipases, and offers insight into mechanisms used to enhance thermal stability which may be of commercial value in engineering lipases for industrial uses. 相似文献
32.
Catanozi S Rocha JC Passarelli M Guzzo ML Alves C Furukawa LN Nunes VS Nakandakare ER Heimann JC Quintão EC 《Journal of lipid research》2003,44(4):727-732
This study aimed at measuring the influence of a low salt diet on the development of experimental atherosclerosis in moderately hyperlipidemic mice. Experiments were carried out on LDL receptor (LDLR) knockout (KO) mice, or apolipoprotein E (apoE) KO mice on a low sodium chloride diet (LSD) as compared with a normal salt diet (NSD). On LSD, the rise of the plasma concentrations of TG and nonesterified fatty acid (NEFA) was, respectively, 19% and 34% in LDLR KO mice, and 21% and 35% in apoE KO mice, and that of plasma cholesterol was limited to the LDLR KO group alone (15%). Probably due to the apoE KO severe hypercholesterolemia, the arterial inner-wall fat storage was not influenced by the diet salt content and was far more abundant in the apoE KO than in the LDLR KO mice. However, in the less severe hypercholesterolemia of the LDLR KO mice, lipid deposits on the LSD were greater than on the NSD. Arterial fat storage correlated with NEFA concentrations in the LDLR KO mice alone (n = 14, P = 0.0065). Thus, dietary sodium chloride restriction enhances aortic wall lipid storage in moderately hyperlipidemic mice. 相似文献
33.
CPEB: a life in translation 总被引:12,自引:0,他引:12
Richter JD 《Trends in biochemical sciences》2007,32(6):279-285
Nearly two decades ago, Xenopus oocytes were found to contain mRNAs harboring a small sequence in their 3' untranslated regions that control cytoplasmic polyadenylation and translational activation during development. This cytoplasmic polyadenylation element (CPE) is the binding platform for CPE-binding protein (CPEB), which promotes polyadenylation-induced translation. Since then, the biochemistry and biology of CPEB has grown rather substantially: mechanistically, CPEB nucleates a complex of factors that regulates poly(A) elongation through, of all things, a deadenylating enzyme; biologically, CPEB mediates many processes including germ-cell development, cell division and cellular senescence, and synaptic plasticity and learning and memory. These observations underscore the growing complexities of CPEB involvement in cell function. 相似文献
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Burken JG Ma X Struckhoff GC Gilbertson A 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(3-4):208-215
Unique sampling techniques have generated a new understanding regarding the fate of volatile organic compounds (VOCs) in phytoremediation systems. Tissue sampling and diffusion traps were used to determine how VOCs are transported in and diffuse from vegetation, particularly woody species. These techniques were then utilized to observe how plants interact with different contaminated media, showing transport of contaminants occurs from the vadose zone (vapor phase) as well as the saturated zone (aqueous phase). Data was gathered in laboratory studies, in native vegetation, and in engineered phytoremediation systems. The findings reveal that diffusion from the xylem tissues to the atmosphere is a major fate for VOCs in phytoremediation applications. Linking VOCs' fate with groundwater hydraulics, mass removal rates from contaminant plumes can be estimated. These techniques were also utilized to observe the impact of engineered plant/microbe systems, which utilize recombinant, root-colonizing organisms to selectively degrade compounds and subsequently alter the fate of VOCs and other organic compounds. The genetically enhanced rhizoremediation methods pose a novel approach that may allow for biodegradation of compounds that formerly were considered recalcitrant. 相似文献
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Robarge MJ Bom DC Tumey LN Varga N Gleason E Silver D Song J Murphy SM Ekema G Doucette C Hanniford D Palmer M Pawlowski G Danzig J Loftus M Hunady K Sherf BA Mays RW Stricker-Krongrad A Brunden KR Harrington JJ Bennani YL 《Bioorganic & medicinal chemistry letters》2005,15(6):1749-1753
The chemoattractant receptor-homologous molecule expressed on T(H)2 cells (CRTH-2), also found on eosinophils and basophils, is a prostaglandin D2 receptor involved in the recruitment of these cell types during an inflammatory response. In this report, we describe the synthesis and optimization of a ramatroban isostere that is a selective and potent antagonist of CRTH-2 which may be useful in the treatment of certain diseases. 相似文献
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39.
Capsule House Sparrows preferred millet over seeds of prairie forbs and grasses native to the USA. By reducing the abundance and availability of some grains, changing agricultural practices may contribute to the population declines of House Sparrows seen in some parts of their range. 相似文献
40.
Llis A. Carlos‐Júnior Matthew Spencer Danilo Mesquita Neves Timothy Peter Moulton Dbora de Oliveira Pires Clovis Barreira e Castro Carlos Renato Rezende Ventura Carlos Eduardo Leite Ferreira Cristiana Silveira Serejo Simone Oigman‐Pszczol Fernanda Araújo Casares Marcelo Checoli Mantelatto Joel Christopher Creed 《Diversity & distributions》2019,25(5):743-757