Search results for "Acetates"
showing 10 items of 94 documents
Significance of pantothenate for glucose fermentation by Oenococcus oeni and for suppression of the erythritol and acetate production.
2001
The heterofermentative lactic acid bacterium Oenococcus oeni requires pantothenic acid for growth. In the presence of sufficient pantothenic acid, glucose was converted by heterolactic fermentation stoichiometrically to lactate, ethanol and CO2. Under pantothenic acid limitation, substantial amounts of erythritol, acetate and glycerol were produced by growing and resting bacteria. Production of erythritol and glycerol was required to compensate for the decreasing ethanol production and to enable the synthesis of acetate. In ribose fermentation, there were no shifts in the fermentation pattern in response to pantothenate supply. In the presence of pantothenate, growing O. oeni contained at l…
Long-term performance of peat biofilters treating ethyl acetate, toluene, and its mixture in air.
2006
Three laboratory-scale peat biofilters were operated at 90 s empty bed residence time (EBRT) for over a year. Biodegradation of ethyl acetate, toluene, or a 1:1 mixture were investigated. In first stage, inlet concentration was progressively increased from 0.4 to 4.5 g/m3. The maximum elimination capacity (EC) found for ethyl acetate was 190 gC/m3·h, and it was not affected by toluene. The maximum EC found for toluene as a sole contaminant was 150 gC/m3·h, but the presence of ethyl acetate decreased the toluene maximum EC to 80 gC/m3·h. From respirometry monitoring, values of 3.19 g CO2/gC and 3.06 g CO2/gC for pure ethyl acetate and pure toluene, respectively, were found, with overall yiel…
Lysine synthesis control in Corynebacterium glutamicum RC 115 in mixed substrate (glucose-acetate) medium.
2003
The effect of acetate as a glucose co-substrate on growth, lysine synthesis and experimental lysine yield from carbon substrates by Corynebacterium glutamicum RC 115 was investigated. It was found that low amounts of acetate, injected with a glucose-acetate pulse into the steady-state continuous culture in bioreactor, caused a slight decrease in the specific rates of glucose uptake and bacterial growth, but a significant increase in the cell specific rate of lysine synthesis and an increase in lysine yield. In contrast, acetate injected in high amounts was followed by a drastic decrease in the values of these parameters. A strong increase in experimental lysine yield under the latter condit…
(R)-NODAGA-PSMA: A Versatile Precursor for Radiometal Labeling and Nuclear Imaging of PSMA-Positive Tumors
2015
Purpose The present study aims at developing and evaluating an urea-based prostate specific membrane antigen (PSMA) inhibitor suitable for labeling with 111In for SPECT and intraoperative applications as well as 68Ga and 64Cu for PET imaging. Methods The PSMA-based inhibitor-lysine-urea-glutamate-coupled to the spacer Phe-Phe-D-Lys(suberoyl) and functionalized with the enantiomerically pure prochelator (R)-1-(1-carboxy-3-carbotertbutoxypropyl)-4,7-carbotartbutoxymethyl)-1,4,7-triazacyclononane ((R)-NODAGA(tBu)3), to obtain (R)-NODAGA-Phe-Phe-D-Lys(suberoyl)-Lys-urea-Glu (CC34). CC34 was labeled with 111In, 68Ga and 64Cu. The radioconjugates were further evaluated in vitro and in vivo in LNC…
Model-based biotechnological potential analysis of Kluyveromyces marxianus central metabolism
2016
Abstract The non-conventional yeast Kluyveromyces marxianus is an emerging industrial producer for many biotechnological processes. Here, we show the application of a biomass-linked stoichiometric model of central metabolism that is experimentally validated, and mass and charge balanced for assessing the carbon conversion efficiency of wild type and modified K. marxianus. Pairs of substrates (lactose, glucose, inulin, xylose) and products (ethanol, acetate, lactate, glycerol, ethyl acetate, succinate, glutamate, phenylethanol and phenylalanine) are examined by various modelling and optimisation methods. Our model reveals the organism’s potential for industrial application and metabolic engi…
Anaerobic central metabolic pathways active during polyhydroxyalkanoate production in uncultured cluster 1Defluviicoccusenriched in activated sludge …
2009
A glycogen nonpolyphosphate-accumulating organism (GAO) enrichment culture dominated by the Alphaproteobacteria cluster 1 Defluviicoccus was investigated to determine the metabolic pathways involved in the anaerobic formation of polyhydroxyalkanoates, carbon storage polymers important for the proliferation of microorganisms in enhanced biological phosphorus removal processes. FISH-microautoradiography and post-FISH fluorescent chemical staining confirmed acetate assimilation as polyhydroxyalkanoates in cluster 1 Defluviicoccus under anaerobic conditions. Chemical inhibition of glycolysis using iodoacetate, and of isocitrate lyase by 3-nitropropionate and itaconate, indicated that carbon is …
Histochemical and biochemical investigations concerning the function of larval oenocytes of Tenebrio molitor L. (Coleoptera, Insecta).
1980
Larval oenocytes of Tenebrio molitor were investigated histochemically. In contrast to the lipid droplets of the fat body, they did not stain with Sudan black. A positive reaction for lipoproteins appeared only after destructive oxidation with sodium hypochlorite. These lipoproteins are the remnants of degenerated membranes, as revealed by ultrastructural analysis. Polyphenols could be identified in the exocuticle of exuvia, and in the newly formed procuticle. Endocuticle, epidermis and oenocytes showed no staining reaction. In oenocytes a great amount of lipase is also present which could be detected with several Tweens as substrates. The significance of these lipases remains unclear, sinc…
Can herbivore-induced volatiles protect plants by increasing the herbivores’ susceptibility to natural pathogens?
2018
In response to insect herbivory, plants mobilize various defenses. Defense responses include the release of herbivore-induced plant volatiles (HIPVs) that can serve as signals to alert undamaged tissues and to attract natural enemies of the herbivores. Some HIPVs can have a direct negative impact on herbivore survival, but it is not well understood by what mechanisms. Here, we tested the hypothesis that exposure to HIPVs renders insects more susceptible to natural pathogens. Exposure of the caterpillars of the noctuid Spodoptera exigua to indole and linalool, but not exposure to (Z)-3-hexenyl acetate, increased the susceptibility to Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV). …
Isomerism of [64Cu-NOTA-Bn]-labeled radiotracers: separation of two complex isomers and determination of their interconversion energy barrier using i…
2011
The model complex [(64)Cu((S)-p-NH(2)-Bn-NOTA)](-) ([(64)Cu]1) was used to study the isomerism of [(64)Cu-NOTA-Bn]-labeled radiotracers. Two complex isomers [(64)Cu]1a and [(64)Cu]1b, which were formed at a ratio of 1:9 during the complexation of [(64)Cu]Cu(2+) with (S)-p-NH(2)-Bn-NOTA, were separated using ion pair chromatography. To study the interconversion, the nonradioactive complex isomers Cu1a and Cu1b were separated and thermally treated at 90 °C in both ammonium acetate solution and deionized water. A faster interconversion rate was observed for both isomers with lower concentrations of ammonium ions. At the end of reaction, the thermodynamic Cu1a to Cu1b equilibrium ratio was 6:94…
Regulatory O 2 tensions for the synthesis of fermentation products in Escherichia coli and relation to aerobic respiration
1997
In an oxystat, the synthesis of the fermentation products formate, acetate, ethanol, lactate, and succinate of Escherichia coli was studied as a function of the O2 tension (pO2) in the medium. The pO2 values that gave rise to half-maximal synthesis of the products (pO0. 5) were 0.2-0.4 mbar for ethanol, acetate, and succinate, and 1 mbar for formate. The pO0.5 for the expression of the adhE gene encoding alcohol dehydrogenase was approximately 0.8 mbar. Thus, the pO2 for the onset of fermentation was distinctly lower than that for anaerobic respiration (pO0.5/= 5 mbar), which was determined earlier. An essential role for quinol oxidase bd in microaerobic growth was demonstrated. A mutant de…