scholarly journals Bubble Column Enables Higher Reaction Rate for Deracemization of ( R,S )‐1‐Phenylethanol with Coupled Alcohol Dehydrogenase/NADH Oxidase System

2019 ◽  
Author(s):  
Mafalda Dias Gomes ◽  
Bettina R. Bommarius ◽  
Shelby R. Anderson ◽  
Brent D. Feske ◽  
John M. Woodley ◽  
...  
Keyword(s):  
Alcohol Dehydrogenase ◽  
Reaction Rate ◽  
Nadh Oxidase ◽  
Bubble Column ◽  
Oxidase System

NADH oxidase system of Agrobacterium tumefaciens

1966 ◽  
Vol 113 (3) ◽  
pp. 548-553 ◽  
Author(s):  
C.K.Ramakrishna Kurup ◽  
C.S. Vaidyanathan ◽  
T. Ramasarma
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Nadh Oxidase ◽  
Oxidase System

Sparged but not stirred: Rapid, ADH-NADH oxidase catalyzed deracemization of alcohols in a bubble column

2020 ◽  
pp. 127909
Author(s):  
Shelby R. Anderson ◽  
Bettina R. Bommarius ◽  
John M. Woodley ◽  
Andreas S. Bommarius
Keyword(s):  
Nadh Oxidase ◽  
Bubble Column

scholarly journals Ubiquinone reduction pattern in pigeon heart mitochondria. Identification of three distinct ubiquinone pools

1985 ◽  
Vol 229 (3) ◽  
pp. 621-629 ◽  
Author(s):  
B M Jørgensen ◽  
H N Rasmussen ◽  
U F Rasmussen
Keyword(s):  
Citric Acid ◽  
Citric Acid Cycle ◽  
Nadh Oxidase ◽  
Heart Mitochondria ◽  
Acid Cycle ◽  
Oxidase System ◽  
Mitochondrial Inner Membrane ◽  
Reducing Conditions ◽  
Endogenous Substrates ◽  
Effect Of Inhibitors

Intact pigeon heart mitochondria showed 10-30% ubiquinone reduction in the absence of substrates. This reduction could not be ascribed to endogenous substrates, as judged by lack of effect of inhibitors and uncouplers and by the very low endogenous respiratory rate. Addition of NADH in the presence of antimycin caused further reduction of about 10% ubiquinone, apparently coupled to the rotenone- and antimycin-sensitive exo-NADH oxidase system [Rasmussen (1969) FEBS Lett. 2, 157-162]. Citric acid cycle substrates reduced most of the remaining ubiquinone in the presence of antimycin; 15-20% of the total ubiquinone content was still in the oxidized form under the most reducing conditions. Three pools of ubiquinone therefore appeared to be present in heart mitochondria: a metabolically inactive pool consisting of reduced as well as oxidized ubiquinone, a pool coupled to oxidation of added (cytoplasmic) NADH, and the well-known pool coupled to citric acid cycle oxidations. Ferricyanide selectively oxidized the ubiquinol reduced by added NADH, indicating that this pool is situated on the outer surface of the mitochondrial inner membrane. Ubiquinone reduction levels were determined with a new method, which is described in detail.

Effect of pH and temperature on alcohol dehydrogenase

1979 ◽  
Vol 44 (3) ◽  
pp. 986-990 ◽  
Author(s):  
Sylva Leblová ◽  
Roman Lapka ◽  
Noemi Nováková
Keyword(s):  
Alcohol Dehydrogenase ◽  
Reaction Rate ◽  
Ethanol Oxidation ◽  
Effect Of Temperature ◽  
Effect Of Ph ◽  
Michaelis Constants ◽  
Pea Seeds ◽  
Increasing Temperature

Alcohol dehydrogenase isolated from germinating pea seeds catalyzes ethanol oxidation at pH 8.7 and acetaldehyde reduction at pH 7.0. The values of the Michaelis constants are the lowest in the range of pH-optimums. The effect of temperature on the reaction rate was investigated over the range 15-55 °C. The initial and maximal rates increase with the increasing temperature and attain a maximum at 40 °C. The values of the Michaelis constants are the lowest at 21 °C. Pea alcohol dehydrogenase looses its activity at 70 °C, the binary enzyme-NAD complex is more thermostable.

Kinetic ethylene glycol assay with use of yeast alcohol dehydrogenase.

1980 ◽  
Vol 26 (9) ◽  
pp. 1278-1280 ◽  
Author(s):  
J H Eckfeldt ◽  
R T Light
Keyword(s):  
Alcohol Dehydrogenase ◽  
Ethylene Glycol ◽  
Trichloroacetic Acid ◽  
Reaction Rate ◽  
Kinetic Assay ◽  
Yeast Alcohol Dehydrogenase ◽  
Stable Temperature ◽  
Narrow Bandwidth ◽  
Ethylene Glycol Poisoning ◽  
Ethanol Determination

Abstract We describe a rapid, accurate, and precise two-point kinetic assay for ethylene glycol. The method involves use of a standard kit for ethanol determination with yeast alcohol dehydrogenase, and of a centrifugal analyzer. Alcohol dehydrogenase catalyzes the oxidation of ethylene glycol in a trichloroacetic acid-precipitated specimen; the resulting NADH production is monitored at 340 nm. The reaction rate is linear with concentration to 1.5 g of ethylene glycol per liter. Interference from methanol, ethanol, and isopropanol was easily recognized after a 30-min incubation at 100 degrees C. We believe that the method can be readily adaptable to any narrow-bandwidth, stable, temperature-controlled spectrophotometer and so should provide more widely for the prompt assessment of patients in whom ethylene glycol poisoning is suspected.

scholarly journals Enzyme Activity of the Cytochrome System of the Egg and Larva of the Cattle Tick (Boophilus Microplus)

1973 ◽  
Vol 26 (2) ◽  
pp. 453 ◽  
Author(s):  
AG Shanahan ◽  
JE O'hagan
Keyword(s):  
Enzyme Activity ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Nadh Oxidase ◽  
Boophilus Microplus ◽  
Cattle Tick ◽  
Oxidase System ◽  
Cytochrome C Reductase ◽  
Nadh Cytochrome ◽  
Eggs And Larvae

The enzymatic activities of the succinate-<;ytochrome c reductase system, the NADH--cytochrome c reductase system, the NADH oxidase system, and cytochrome c oxidase were determined spectrophotometrically in particulate preparations of eggs and larvae of B. micro plus.

The intracellular Na+ and K+ composition of the moderately halophilic bacterium, Paracoccus halodenitrificans

1980 ◽  
Vol 26 (4) ◽  
pp. 496-502 ◽  
Author(s):  
M. Sadler ◽  
M. McAninch ◽  
R. Alico ◽  
L. I. Hochstein
Keyword(s):  
Stationary Phase ◽  
Growth Medium ◽  
Nadh Oxidase ◽  
Halophilic Bacterium ◽  
Oxidase System ◽  
Final Value ◽  
Moderately Halophilic Bacterium ◽  
Nacl Concentration ◽  
Atp Pool ◽  
Membrane Bound

The intracellular concentrations of Na+ and K+ in exponentially growing Paracoccus halodenitrificans were independent of the NaCl concentration of the growth medium. The observed values were approximately 100 and 300 mM for Na+ and K+, respectively. In stationary phase cells, the ultimate values for Na+ depended on the NaCl concentration of the growth medium. With cells grown in the presence of 1 M NaCl, the value was about 500 mM; for cells grown in the presence of 3 M NaCl, the value was about 1.1 M. The K+ concentration in stationary phase cells was unaffected by the NaCl concentration in the growth medium. The final value was about 100 mM. Associated with these changes were changes in the ATP pool and decreases in the activities of the NADH oxidase system and the membrane-bound ATPase. It is proposed that the decrease in the activities of these enzymes may account for the ion flows observed in stationary phase cells.

Search for Millimeter Microwave Effects on Enzyme or Protein Functions

1979 ◽  
Vol 34 (1-2) ◽  
pp. 60-63 ◽  
Author(s):  
P. Tuengler ◽  
F. Keilmann ◽  
L. Genzel
Keyword(s):  
Alcohol Dehydrogenase ◽  
Microwave Irradiation ◽  
Reaction Rate ◽  
Cooperative Binding ◽  
Irradiation Intensity ◽  
Biological Responses ◽  
Protein Functions ◽  
Microwave Effects

Abstract Recent observations of nonthermal, resonant biological responses to weak millimeter microwave irradiation have led us to investigate whether similar influences exist on enzymatic functions in vitro. We chose (i) the reduction of ethanol in the presence of alcohol dehydrogenase and (ii) the cooperative binding of oxygen on hemoglobin. Using an irradiation intensity near 10 mW/cm2 the frequency was continuously varied from 40 to 115 GHz with a resolution of a few MHz. No micro­ wave influences were detectable within our experimental sensitivity of about 0.1% of the reaction rate in (i), or of the amount of bound oxygen at half saturation in (ii).

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