Journal:

Article Title: Oxidation of Methyl tert -Butyl Ether by Alkane Hydroxylase in Dicyclopropylketone-Induced and n -Octane-Grown Pseudomonas putida GPo1

doi: 10.1128/AEM.70.8.4544-4550.2004

Figure Lengend Snippet: Inhibition of MTBE oxidation by DCPK-treated cells of P. putida GPo1 by gaseous n-alkanes. Cells (4.4 mg of total protein) of strain GPo1 grown on rich medium with DCPK were incubated in glass serum vials (10 ml) in the presence of MTBE (42 μmol) as described in Materials and Methods. Shown is the time course for TBA production from MTBE for cells incubated with MTBE alone (▪) or with MTBE and methane (▵), ethane (▴), propane (○), or n-butane (•). Each gaseous n-alkane was added to an initial gas phase concentration of 50% (vol/vol). (Inset) Cells (3.2 mg of total protein) of strain GPo1 grown on rich medium with DCPK were incubated for 30 min in glass serum vials (10 ml) in the presence of MTBE (42 μmol) and various gas phase concentrations of propane and n-butane as described in Materials and Methods. Shown are the effects of various dissolved concentrations of propane (•) and n-butane (○) on the rate of TBA production. Also shown is the resulting curve when the results for each culture were computer fitted to a single substrate-binding model {y = Vmax · [x/(Ks + x)]}. The error bars represent the range of values for two different cultures of cells grown on each substrate.

Article Snippet: For instance, camphor-grown cells of Pseudomonas putida (ATCC 17453) oxidized low MTBE concentrations (20 ppm [∼200 μM MTBE in solution]).

Techniques: Inhibition, Incubation, Concentration Assay, Binding Assay

Journal:

Article Title: Oxidation of Methyl tert -Butyl Ether by Alkane Hydroxylase in Dicyclopropylketone-Induced and n -Octane-Grown Pseudomonas putida GPo1

doi: 10.1128/AEM.70.8.4544-4550.2004

Figure Lengend Snippet: Oxidation of MTBE by DCPK-treated cells of P. putida GPo1. Washed cells (∼18 mg of total protein) of strain GPo1 grown on PCM with DCPK were incubated in phosphate buffer (25 ml) in a glass serum vial (160 ml) sealed with a butyl rubber stopper and an aluminum crimp seal. The vials contained either MTBE (28 μmol; ∼900 μM MTBE in solution) or TBA (28 μmol; ∼1.1 mM TBA in solution). At the indicated times, samples (2 μl) were removed from the reaction medium and analyzed for MTBE consumption and TBA production by gas chromatography and additional samples (500 μl) were also removed for quantification of formaldehyde as described in Materials and Methods. Shown is the time course for MTBE consumption (▪), TBA production (□), and formaldehyde production (•) for cells incubated with MTBE. Also shown is the percentage of MTBE consumed that was detected as TBA for cells incubated with MTBE (○), the residual TBA in reaction mixtures in which cells were incubated with TBA alone (⧫), and the residual TBA in a reaction vial with TBA alone (▴). The data are plotted as the average of two separate cultures. The error bars show the range of the individual data points.

Article Snippet: For instance, camphor-grown cells of Pseudomonas putida (ATCC 17453) oxidized low MTBE concentrations (20 ppm [∼200 μM MTBE in solution]).

Techniques: Incubation, Gas Chromatography

Journal:

Article Title: Oxidation of Methyl tert -Butyl Ether by Alkane Hydroxylase in Dicyclopropylketone-Induced and n -Octane-Grown Pseudomonas putida GPo1

doi: 10.1128/AEM.70.8.4544-4550.2004

Figure Lengend Snippet: Inhibition of MTBE oxidation by DCPK-treated cells of P. putida GPo1. Cells (3.8 to 5 mg of total protein) of strain GPo1 grown on rich medium with DCPK were incubated in glass serum vials (10 ml) in the presence of MTBE (5.5 μmol) for 30 min as described in Materials and Methods. Shown is the average inhibition of TBA production in the presence of each tested n-alkane or 1,7-octadiyne. Each of the n-alkanes and 1,7-octadiyne were added to an initial concentration of 0.1% (vol/vol) of the reaction medium (1 ml). The error bars indicate the standard error of values obtained from a minimum of four replicate incubations conducted with different cell cultures.

Article Snippet: For instance, camphor-grown cells of Pseudomonas putida (ATCC 17453) oxidized low MTBE concentrations (20 ppm [∼200 μM MTBE in solution]).

Techniques: Inhibition, Incubation, Concentration Assay

Journal:

Article Title: Oxidation of Methyl tert -Butyl Ether by Alkane Hydroxylase in Dicyclopropylketone-Induced and n -Octane-Grown Pseudomonas putida GPo1

doi: 10.1128/AEM.70.8.4544-4550.2004

Figure Lengend Snippet: Kinetics of MTBE oxidation by DCPK-treated and n-octane-grown cells of P. putida GPo1. Cells of strain GPo1 were grown on PCM with DCPK and n-octane (0.05%, vol/vol) in G4 mineral salts medium as described in Materials and Methods. Cells (1.1 to 2.1 mg of total protein) were incubated with a range of dissolved MTBE concentrations (0 to ∼50 mM) for 30 min, and the amount of TBA generated was detected by gas chromatography as described in Materials and Methods. Reaction rates for DCPK-treated cells (▪) and n-octane-grown cells (▾) were calculated from the amount of TBA detected after 30 min, assuming that no oxidation of TBA occurred during the reaction. Shown is the resulting curve when the results for each culture were computer fitted to a single substrate-binding model {y = Vmax · [x/(Ks + x)]}. The error bars represent the range of values for two different cultures of cells grown on each substrate.

Article Snippet: For instance, camphor-grown cells of Pseudomonas putida (ATCC 17453) oxidized low MTBE concentrations (20 ppm [∼200 μM MTBE in solution]).

Techniques: Incubation, Generated, Gas Chromatography, Binding Assay