Steady-state kinetics and the inactivation by 2,3-butanedione of the energy-independent transhydrogenase of Escherichia coli cell membranes

1979 ◽  
Vol 571 (2) ◽  
pp. 201-217 ◽  
Author(s):  
Mona Homyk ◽  
P.D. Bragg
Keyword(s):  
Escherichia Coli ◽  
Steady State ◽  
Cell Membranes ◽  
Coli Cell ◽  
Steady State Kinetics

scholarly journals Chorismate synthase. Pre-steady-state kinetics of phosphate release from 5-enolpyruvylshikimate 3-phosphate

1990 ◽  
Vol 265 (3) ◽  
pp. 899-902 ◽  
Author(s):  
T R Hawkes ◽  
T Lewis ◽  
J R Coggins ◽  
D M Mousdale ◽  
D J Lowe ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Steady State ◽  
Lag Phase ◽  
Chorismate Synthase ◽  
Phosphate Release ◽  
Rate Limiting Step ◽  
Limiting Step ◽  
Steady State Kinetics ◽  
Rate Limiting ◽  
Kinetics Of

The pre-steady-state kinetics of phosphate formation from 5-enolpyruvylshikimate 3-phosphate catalysed by Escherichia coli chorismate synthase (EC 4.6.1.4) were studied by a rapid-acid-quench technique at 25 degrees C at pH 7.5. No pre-steady-state ‘burst’ or ‘lag’ phase was observed, showing that phosphate is released concomitant with the rate-limiting step of the enzyme. The implications of this result for the mechanism of action of chorismate synthase are discussed.

Threonine synthesis from aspartate in Escherichia coli cell-free extracts: pathway dynamics

2001 ◽  
Vol 356 (2) ◽  
pp. 425-432 ◽  
Author(s):  
Badr RAÏS ◽  
Christophe CHASSAGNOLE ◽  
Thierry LETELLIER ◽  
David A. FELL ◽  
Jean-Pierre MAZAT
Keyword(s):  
Escherichia Coli ◽  
Steady State ◽  
Time Dependence ◽  
Experimental Model ◽  
Crude Extract ◽  
Coli Cell ◽  
Quasi Steady State ◽  
Physiological Conditions ◽  
Intermediate Metabolites ◽  
Narrow Concentration Range

We have developed an experimental model of the whole threonine pathway that allows us to study the production of threonine from aspartate under different conditions. The model consisted of a desalted crude extract of Escherichia coli to which we added the substrates and necessary cofactors of the pathway: aspartate, ATP and NADPH. In this experimental model we measured not only the production of threonine, but also the time dependence of all the intermediate metabolites and of the initial substrates, aspartate, ATP and NADPH. A stoichiometric conversion of precursors into threonine was observed. We have derived conditions in which a quasi steady state can be transiently observed and used to simulate physiological conditions of functioning of the pathway in the cell. The dependence of threonine synthesis and of the aspartate and NADPH consumption on the initial aspartate and threonine concentrations exhibits greater sensitivity to the aspartate concentration than to the threonine concentration in these non-steady-state conditions. A response to threonine is only observed in a narrow concentration range from 0.23 to 2mM.

Response of Escherichia coli cell membranes to induction of ? c1857 prophage by heat shock

1991 ◽  
Vol 5 (12) ◽  
pp. 2935-2945 ◽  
Author(s):  
K. Kucharczyk ◽  
E. Laskowska ◽  
A. Taylor
Keyword(s):  
Escherichia Coli ◽  
Heat Shock ◽  
Cell Membranes ◽  
Coli Cell

scholarly journals Characterization of Neurospora crassa catabolic dehydroquinase purified from N. crassa and Escherichia coli

1982 ◽  
Vol 203 (3) ◽  
pp. 769-773 ◽  
Author(s):  
A R Hawkins ◽  
W R Reinert ◽  
N H Giles
Keyword(s):  
Escherichia Coli ◽  
Steady State ◽  
Neurospora Crassa ◽  
Protein Sequence ◽  
Sequence Data ◽  
E Coli ◽  
Steady State Kinetics ◽  
Electrophoretic Data ◽  
Protein Sequence Data

1. Neurospora crassa catabolic dehydroquinase has been purified from N. crassa and Escherichia coli. 2. Protein-sequence and gel-electrophoretic data show that apparently pure, homogeneous native dehydroquinase is a mixture of intact and proteinase-cleaved enzyme monomers. 3. Protein-sequence data and steady-state kinetics show that the catabolic dehydroquinase gene of N. crassa is expressed with fidelity in E. coli.

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