Cloning and expression of the fumarate reductase gene of Escherichia coli

1981 ◽  
Vol 59 (3) ◽  
pp. 158-164 ◽  
Author(s):  
Elke Lohmeier ◽  
D. Scott Hagen ◽  
Peter Dickie ◽  
Joel H. Weiner

Mutants of Escherichia coli deficient in fumarate reductase activity and therefore unable to grow anaerobically with fumarate as an electron acceptor have been isolated. By F+-mediated conjugation and complementation with the mutant host, two E. coli: Col E1 recombinant DNA plasmids have been identified from the Clarke and Carbon Colony Bank which carry the structural genes for fumarate reductase. Bacteria harboring either of these plasmids express about ten times the normal level of fumarate reductase. Enzyme purified from the two sources, plasmid-carrying and plasmidless E. coli, have identical physical and kinetic properties indicating that both the 69 000 and 25 000 dalton polypeptides are amplified. Regulation of plasmid-encoded enzyme, like the chromosomally encoded enzyme, is dependent upon the presence of fumarate and anaerobiosis.

Genetics ◽  
1990 ◽  
Vol 125 (4) ◽  
pp. 691-702 ◽  
Author(s):  
B L Berg ◽  
V Stewart

Abstract Formate oxidation coupled to nitrate reduction constitutes a major anaerobic respiratory pathway in Escherichia coli. This respiratory chain consists of formate dehydrogenase-N, quinone, and nitrate reductase. We have isolated a recombinant DNA clone that likely contains the structural genes, fdnGHI, for the three subunits of formate dehydrogenase-N. The fdnGHI clone produced proteins of 110, 32 and 20 kDa which correspond to the subunit sizes of purified formate dehydrogenase-N. Our analysis indicates that fdnGHI is organized as an operon. We mapped the fdn operon to 32 min on the E. coli genetic map, close to the genes for cryptic nitrate reductase (encoded by the narZ operon). Expression of phi(fdnG-lacZ) operon fusions was induced by anaerobiosis and nitrate. This induction required fnr+ and narL+, two regulatory genes whose products are also required for the anaerobic, nitrate-inducible activation of the nitrate reductase structural gene operon, narGHJI. We conclude that regulation of fdnGHI and narGHJI expression is mediated through common pathways.


Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 13
Author(s):  
Elena Forte ◽  
Sergey A. Siletsky ◽  
Vitaliy B. Borisov

Interaction of two redox enzymes of Escherichia coli, cytochrome bo3 and cytochrome bd-I, with ammonium sulfate/ammonia at pH 7.0 and 8.3 was studied using high-resolution respirometry and absorption spectroscopy. At pH 7.0, the oxygen reductase activity of none of the enzymes is affected by the ligand. At pH 8.3, cytochrome bo3 is inhibited by the ligand, with 40% maximum inhibition at 100 mM (NH4)2SO4. In contrast, the activity of cytochrome bd-I at pH 8.3 increases with increasing the ligand concentration, the largest increase (140%) is observed at 100 mM (NH4)2SO4. In both cases, the effector molecule is apparently not NH4+ but NH3. The ligand induces changes in absorption spectra of both oxidized cytochromes at pH 8.3. The magnitude of these changes increases as ammonia concentration is increased, yielding apparent dissociation constants Kdapp of 24.3 ± 2.7 mM (NH4)2SO4 (4.9 ± 0.5 mM NH3) for the Soret region in cytochrome bo3, and 35.9 ± 7.1 and 24.6 ± 12.4 mM (NH4)2SO4 (7.2 ± 1.4 and 4.9 ± 2.5 mM NH3) for the Soret and visible regions, respectively, in cytochrome bd-I. Consistently, addition of (NH4)2SO4 to cells of the E. coli mutant containing cytochrome bd-I as the only terminal oxidase at pH 8.3 accelerates the O2 consumption rate, the highest one (140%) being at 27 mM (NH4)2SO4. We discuss possible molecular mechanisms and physiological significance of modulation of the enzymatic activities by ammonia present at high concentration in the intestines, a niche occupied by E. coli.


1982 ◽  
Vol 45 (3) ◽  
pp. 241-243 ◽  
Author(s):  
M. KRUK ◽  
J. S. LEE

Trimethylamine-N-oxide (TMA-O) reductase activity of resting cells of Escherichia coli was inhibited by tetrasodium ethylenediaminetetraacetate (Na4EDTA), benzoic acid (BA and methylparaben (MP). The 50% inhibitory concentrations of Na4EDTA, BA and MP were 20.2, 1.2 and 32.4 mM, respectively. BA at pH 6.5 or below most effectively inhibited the TMA-O reductase. Sorbic acid (SA), up to 0.70 mM, had no effect on TMA-O reductase activity, but SA inhibited the growth and subsequent TMA production in E. coli at or above 0.3S mM.


1985 ◽  
Vol 95 (3) ◽  
pp. 611-618
Author(s):  
Naomi Datta

SUMMARYThe study of Escherichia coli and its plasmids and bacteriophages has provided a vast body of genetical information, much of it relevant to the whole of biology. This was true even before the development of the new techniques, for cloning and analysing DNA, that have revolutionized biological research during the past decade. Thousands of millions of dollars are now invested in industrial uses of these techniques, which all depend on discoveries made in the course of academic research on E. coli. Much of the background of knowledge necessary for the cloning and expression of genetically engineered information, as well as the techniques themselves, came from work with this organism.


1989 ◽  
Vol 35 (4) ◽  
pp. 487-491 ◽  
Author(s):  
Paul H. Goodwin

Xylella fastidiosa DNA, partially digested with Sau3A, was ligated into the cosmid vector, pUCD615. Approximately 4500 ampicillin-resistant Escherichia coli colonies were obtained. The frequency of complementation of leucine auxotrophy in transfected E. coli indicated that the cosmid gene bank was representative of X. fastidiosa genomic DNA. Colonies were lysed directly onto nitrocellulose membranes using a thermo-inducible λ lysogen and screened for expression of X. fastidiosa antigens. Approximately 16.5% of a random sample of clones were found to express X. fastidiosa antigens as determined by Western blots. These proteins comigrated with proteins of X. fastidiosa and ranged in molecular weight from 10 000 to 160 000. Conjugation of several of the plasmids into Erwinia stewartii resulted in expression of the similar molecular weight cloned proteins with similar levels of expression as in E. coli.Key words: Xylella fastidiosa, Pierce's disease, immunological clone screening, thermo-inducible lysogeny.


1986 ◽  
Vol 69 (3) ◽  
pp. 531-536
Author(s):  
Walter E Hill ◽  
Barry A Wentz ◽  
William L Payne ◽  
James A Jagow ◽  
Gerald Zon ◽  
...  

Abstract The genes that encode several of the enterotoxins produced by Escherichia coli have been cloned by recombinant DNA techniques. When the nucleotide sequence of these genes is determined, defined sequence oligonucleotides that include a part of these genes may be synthesized. A 22-base DNA hybridization probe was produced for each of 2 heatstable E. coli enterotoxin (ST) genes: STH, from strains originally isolated from humans; and STP, from strains first found in pigs. For this study, 32P end-labeled DNA probes, sonicated calf thymus DNA, and 3 known and 20 unknown (10 ST-positive and 10 ST-negative) strains were sent to each of 23 collaborators. Cultures were spotted onto an agar-based medium and grown into colonies, which were transferred by blotting to cellulose filters, lysed by alkali and steam, and used for DNA colony hybridization with the ST DNA probes. Strains containing an ST gene were recognized as dark spots on an autoradiogram. Of the 460 samples analyzed, 440 (95.7%) were correctly classified by the collaborators. The method has been adopted official first action.


2010 ◽  
Vol 76 (7) ◽  
pp. 2107-2114 ◽  
Author(s):  
Qingzhao Wang ◽  
Mark S. Ou ◽  
Y. Kim ◽  
L. O. Ingram ◽  
K. T. Shanmugam

ABSTRACT During anaerobic growth of Escherichia coli, pyruvate formate-lyase (PFL) and lactate dehydrogenase (LDH) channel pyruvate toward a mixture of fermentation products. We have introduced a third branch at the pyruvate node in a mutant of E. coli with a mutation in pyruvate dehydrogenase (PDH*) that renders the enzyme less sensitive to inhibition by NADH. The key starting enzymes of the three branches at the pyruvate node in such a mutant, PDH*, PFL, and LDH, have different metabolic potentials and kinetic properties. In such a mutant (strain QZ2), pyruvate flux through LDH was about 30%, with the remainder of the flux occurring through PFL, indicating that LDH is a preferred route of pyruvate conversion over PDH*. In a pfl mutant (strain YK167) with both PDH* and LDH activities, flux through PDH* was about 33% of the total, confirming the ability of LDH to outcompete the PDH pathway for pyruvate in vivo. Only in the absence of LDH (strain QZ3) was pyruvate carbon equally distributed between the PDH* and PFL pathways. A pfl mutant with LDH and PDH* activities, as well as a pfl ldh double mutant with PDH* activity, had a surprisingly low cell yield per mole of ATP (Y ATP) (about 7.0 g of cells per mol of ATP) compared to 10.9 g of cells per mol of ATP for the wild type. The lower Y ATP suggests the operation of a futile energy cycle in the absence of PFL in this strain. An understanding of the controls at the pyruvate node during anaerobic growth is expected to provide unique insights into rational metabolic engineering of E. coli and related bacteria for the production of various biobased products at high rates and yields.


1979 ◽  
Vol 57 (6) ◽  
pp. 813-821 ◽  
Author(s):  
Peter Dickie ◽  
Joel H. Weiner

Fumarate reductase has been purified 100-fold to 95% homogeneity from the cytoplasmic membrane of Escherichia coli, grown anaerobically on a defined medium containing glycerol plus fumarate. Optimal solubilization of total membrane protein and fumarate reductase activity occurred with nonionic detergents having a hydrophobic–lipophilic balance (HLB) number near 13 and we routinely solubilized the enzyme with Triton X-100 (HLB number = 13.5). Membrane enzyme extracts were fractionated by hydrophobic-exchange chromatography on phenyl Sepharose CL-4B to yield purified enzyme. The enzyme, whether membrane bound, in Triton extracts, or purified, had an apparent Km near 0.42 mM. Two peptides with molecular weights of 70 000 and 24 000, present in 1:1 molar ratios, were identified by sodium dodecyl sulfate polyacrylamide slab-gel electrophoresis to coincide with enzyme activity. A minimal native molecular weight of 100 000 was calculated for fumarate reductase by Sephacryl S-200 gel filtration in the presence of sodium cholate. This would indicate that the enzyme is a dimer. The purified enzyme has low, but measurable, succinate dehydrogenase activity.


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