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711.
Zhenwei Qiu Yongbing Zhang Dorothea Bedigian Xiao Li Changsui Wang Hongen Jiang 《Economic botany》2012,66(3):255-263
Sesame Utilization in China: New Archaeobotanical Evidence from Xinjiang. A cache of sesame (Sesamum indicum L.) seeds, discovered in the Thousand Buddha Grottoes at Boziklik, Turpan, China, dating to ca. 700 years before present (BP), is hard evidence of their use in China since that time. Morphological and anatomical features suggest a white sesame cultivar. The sizeable quantity unearthed implies that sesame was a valued commodity that could provision the monks and enrich the diet of ancient inhabitants as an oil source. 相似文献
712.
713.
Yuxiang Yao Hongzhi Tang Huixue Ren Hao Yu Lijuan Wang Ping Xu 《Journal of bacteriology》2012,194(20):5714-5715
We announce a 4.63-Mb genome assembly of an isolated bacterium that is the first sequenced nicotine-degrading Arthrobacter strain. Nicotine catabolism genes of the nicotine-degrading plasmid pAO1 were predicted, but plasmid function genes were not found. These results will help to better illustrate the molecular mechanism of nicotine degradation by Arthrobacter. 相似文献
714.
A. Yu. Gulevich A. Yu. Skorokhodova A. A. Morzhakova S. V. Antonova A. V. Sukhozhenko R. S. Shakulov V. G. Debabov 《Applied Biochemistry and Microbiology》2012,48(4):344-349
Anaerobic biosynthesis of 1-butanol from glucose is investigated in recombinant Escherichia coli strains which form butyryl-CoA using the heterologous enzyme complex of clostridia or as a result of a reversal in the action of native enzymes of the fatty acid β-oxidation pathway. It was revealed that when the basic pathways of acetic and lactic acid formation are inactivated due to deletions of the ackA, pta, poxB, and ldhA genes, the efficiency of butyryl-CoA biosynthesis and its reduced product, i.e., 1-butanol, by two types of recombinant stains is comparable. The limiting factor for 1-butanol production by the obtained strains is the low substrate specificity of the basic CoA-dependent alcohol/aldehyde dehydrogenase AdhE from E. coli to butyryl-CoA. It was concluded that, in order to construct an efficient 1-butanol producer based on a model strain synthesizing butyryl-CoA as a result of reversed action of fatty acid β-oxidation enzymes, it is necessary to provide intensive formation of acetyl-CoA and enhanced activity of alternative alcohol and aldehyde dehydrogenases in the cells of a strain. 相似文献
715.
T. P. Pirog T. A. Shevchuk A. D. Konon E. Yu. Dolotenko 《Applied Biochemistry and Microbiology》2012,48(6):569-576
The effect of fumarate (C4-dicarboxylic acid, a gluconeogenesis precursor) and citrate (a lipid synthesis regulator) on the production of surfactants by Acinetobacter calcoaceticus K-4 grown on ethanol has been studied. Simultaneous addition of fumarate and citrate to concentrations of 0.01–0.02% at the end of the exponential phase of K-4 growth in a medium with 2 vol % ethanol increases the conditional surfactant concentration by 45–55% in comparison with indices in medium without organic acids. The increased level of surfactant production in the presence of fumarate and citrate is determined by the increase in the activities of enzymes involved in the production of glycolipids (phosphoenolpyruvate synthase and trehalose phosphate synthase) and aminolipids (NADP+-dependent glutamate dehydrogenase) in of 1.7–7 times, as well as by the simultaneous functioning of two anaplerotic pathways: the glyoxylate cycle and the reaction catalyzed by phosphoenolpyruvate carboxylase. 相似文献
716.
Viscoelastic properties of relaxed rat papillary muscles in physiological hypertrophy (intensive swimming for 5 weeks) have been obtained. It has been ascertained that viscoelastic properties of hypertrophied muscles are not significantly distinguished from those of control papillary muscles. A three-dimensional model of myocardial fascicle has been verified in compliance with experimental data of biomechanical tests of hypertrophied muscles. Elastic and viscous parameters of structural elements of the model negligibly differ from the parameters of the model of a control muscle. It is shown that physiological hypertrophy has a slight influence on viscoelastic properties of papillary muscles. 相似文献
717.
718.
719.
Early to late Pliocene sedimentary strata present across the northern Bass Strait hinterland, southeastern Australia yield extensive fossil proxy data relevant to the interpretation of high sea level coastal palaeomorphology. Within the Pliocene Whalers Bluff Formation exposed in coastal cliffs near the township of Portland, Victoria, marine microfossil faunas delineate two broad cycles of deposition. Both these sedimentary cycles are bound below by unconformity surfaces. Within the lower sedimentary cycle, a basal stress-tolerant (low diversity) marginal marine microfossil fauna devoid of ostracods and suggestive of bottom-water hypoxia, is succeeded by a diverse shallow marine ostracod fauna dominated by stenohaline species indicative of a sheltered (but open) oceanic embayment. This lower sedimentary cycle has an early Pliocene (Zanclean) age. Equivalent shallow marine (e.g. coastal embayment) deposits occur broadly across the coastal hinterland of southeastern Australia—reflecting the generally higher global sea levels of this time. The upper cycle in the cliff exposures at Portland is late Pliocene (Piacenzian) in age. Equivalent deposits across the Bass Strait hinterland are restricted to former incised river valley settings. Euryhaline estuarine/coastal lagoon Ostracoda are present throughout the upper cycle in the Portland cliffs. These are associated with a low diversity microfauna at the base of the upper cycle and a high diversity microfauna towards the top of the cycle. Early Pliocene coastal marine deposits can be distinguished from late Pliocene coastal marine deposits across the northern Bass Strait hinterland on the basis of the presence or absence of certain open marine (‘stenohaline’) ostracod species. 相似文献
720.
The hypothesis that nitrate versus phosphate regulates the coastal primary production has been assessed at different time scales in the northwest Alboran Sea. Time series of temperature, salinity, nutrients and chlorophyll a obtained at three stations located off Málaga city (the greatest coastal urban core along the Alboran Sea shoreline) from 1992 to 2006 have been analysed. At the decadal scale, temperature increased linearly while salinity decreased. These changes were related to a shift in the wind regime suggesting that coastal upwelling became steadily weaker. In contrast to phosphate, nitrate was positively correlated with salinity at the seasonal scale and decreased linearly from 1992 to 2006. Seasonal and decadal changes in chlorophyll a were correlated with nitrate (and uncorrelated with phosphate). However, non-regular variability in chlorophyll a was correlated with phosphate. Consequently, the results demonstrate that nitrate controls the phytoplankton biomass at the inter-annual scale while both nitrate and phosphate do so at a shorter time scale. The Bay of Málaga receives elevated entries of domestic waste waters that release high loads of phosphate compared to nitrate. Our analysis indicates that the expected impact of this pollution on chlorophyll a at the inter-annual scale is reduced in comparison with the effects of atmospheric forcing. 相似文献