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C. L. Keith R. L. Bridges L. R. Fina K. L. Iverson J. A. Cloran 《Archives of microbiology》1978,118(2):169-172
Anaerobic rupture of the benzoic acid ring was investigated. Carbon 4 was converted primarily to carbon dioxide. Following ring rupture during methane fermentation, propanoic acid is an intermediate, and carbon 4 of benzoate becomes its carboxyl.Contribution No. 1285-j, Division of Biology, Kansas State University, Manhattan, KS 66506. This work was supported in part by funds from the Kansas Agricultural Experiment Station, Kansas State University, Manhattan, KS 66506. Paper II of this series is Fina and Fiskin (1960) 相似文献
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Janine F. Bridges Peter C. Millard John F. Woodley 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,544(2):448-451
The uptake of free and liposome-entrapped 125I-labelled poly(vinylpyrrolidone) was measured in an intestinal sac preparation from adult rats. An an equal concentration of 125I-labelled poly(vinylpyrrolidone), the rate of uptake of the liposome-entrapped material was four times that of the free macromolecule. 相似文献
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zge Karayel Francesca Tonelli Sebastian Virreira Winter Phillip E. Geyer Ying Fan Esther M. Sammler Dario R. Alessi Martin Steger Matthias Mann 《Molecular & cellular proteomics : MCP》2020,19(9):1546-1560
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- •MS-based clinical assay that accurately determines phospho Rab10 occupancy.
- •Stable isotope labeled phosphopeptide injected as a standard with endogenous tryptic phospho Rab peptide for accurate ratio determination.
- •Determination of pRab levels in neutrophils of Parkinson disease patients.
- •Relevance of pRab levels as marker of PD.
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Food subsidies have the potential to modify ecosystems and affect the provision of goods and services. Predictable Anthropogenic Food Subsidies (PAFS) modify ecosystems by altering ecological processes and food webs. The global concern over the effects of PAFS in ecosystems has led to development of environmental policies aimed at curbing the production or ultimately banning of PAFS. However, the effects of reducing or banning PAFS are not known. We explore the consequences of PAFS removal in a marine ecosystem under two scenarios: 1) gradual reduction, or 2) an abrupt ban, using a mass balance model to test these hypotheses–The reduction or loss of PAFS will: i) modify trophic levels and food webs through effects on foraging by opportunistic species, ii) increase the resilience of opportunistic species to food shortages, and iii) modify predator–prey interactions through shifts in prey consumption. We found that PAFS lower the trophic levels of opportunistic scavengers and increase their food pathways. Scavengers are able to switch prey when PAFS are reduced gradually but they decline when PAFS are abruptly banned. PAFS reduction to a certain minimal level causes a drop in the ecosystem’s stability. We recommend gradual reduction of PAFS to a minimal level that would maintain the ecosystem’s stability and allow species exploiting PAFS to habituate to the food subsidy reduction. 相似文献
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J T Rogers K R Bridges G P Durmowicz J Glass P E Auron H N Munro 《The Journal of biological chemistry》1990,265(24):14572-14578
Interleukin-1 (IL-1 beta) increases the synthesis of both heavy and light (L)-ferritin subunits when added to human hepatoma cells (HepG2) grown in culture. RNase protection and Northern blot analysis with L-ferritin probes revealed that no changes in L-ferritin mRNA levels occur after cytokine stimulation. However, the induction coincides with an increased association of the L-subunit mRNA with polyribosomes. Since the recruitment of stored ferritin mRNA onto polyribosomes is seen when iron enters the cell, the effect of IL-1 beta on iron uptake was tested and was found to be unaffected by the lymphokine. Neither transferrin receptor mRNA levels nor the number of receptors displayed on the cell surface was affected by IL-1 beta. However, the action of the cytokine on ferritin translation is inhibited by the action of the intracellular iron chelator deferoxamine. These data indicate that IL-1 beta induces ferritin gene expression by translational control of its mRNA. The pathway of induction is different from iron-dependent ferritin gene expression whereas regulation requires the background presence of cellular iron. 相似文献
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Specificity of mutation by UV light and delayed photoreversal in umuC-defective Escherichia coli K-12: a targeting intermediate at pyrimidine dimers. 总被引:1,自引:1,他引:0
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Prototrophic mutants produced by UV light in Escherichia coli K-12 strains with argE3(Oc) and hisG4(Oc) defects are distinguished as backmutations and specific nonsense suppressor mutations. In strains carrying a umuC defect, mutants are not produced unless irradiated cells are incubated and then exposed to photoreversing light (delayed photoreversal mutagenesis). The mutants thus produced are found to be specifically suppressor mutations and not backmutations. The suppressor mutations are primarily glutamine tRNA ochre suppressor mutations, which have been attributed previously to mutation targeted at T = C pyrimidine dimers. In a lexA51 recA441 strain, where the SOS mutagenesis functions are constitutive, targeting at dimers is confirmed by demonstrating that the induction of glutamine tRNA suppressor mutations is susceptible to photoreversal. In the same strain induction of backmutations is not susceptible to photoreversal. Thus delayed photoreversal mutagenesis produces suppressor mutations that can be targeted at pyrimidine dimers and does not produce backmutations that are not targeted at pyrimidine dimers. This correlation supports the idea that delayed photoreversal mutagenesis in umuC defective cells reflects a mutation process arrested at a targeting pyrimidine dimer photoproduct, which is the immediate cause of both the alteration in DNA sequence and the obstruction (unless repaired) to mutation fixation and ultimate expression. 相似文献