| Title |
Nitrate reductases inEscherichia coli
|
|---|---|
| Published in |
Antonie van Leeuwenhoek, March 1994
|
| DOI | 10.1007/bf00871632 |
| Pubmed ID | |
| Authors |
Violaine Bonnefoy, John A. Demoss |
| Abstract |
Escherichia coli expresses two different membrane-bound respiratory nitrate reductases, nitrate reductase A (NRA) and nitrate reductase Z (NRZ). In this review, we compare the genetic control, biochemical properties and regulation of these two closely related enzyme systems. The two enzymes are encoded by distinct operons located within two different loci on the E. coli chromosome. The narGHJI operon, encoding nitrate reductaseA, is located in the chlC locus at 27 minutes, along with several functionally related genes: narK, encoding a nitrate/nitrite antiporter, and the narXL operon, encoding a nitrate-activated, two component regulatory system. The narZYWV operon, encoding nitrate reductase Z, is located in the chlZ locus located at 32.5 minutes, a region which includes a narK homologue, narU, but no apparent homologue to the narXL operon. The two membrane-bound enzymes have similar structures and biochemical properties and are capable of reducing nitrate using normal physiological substrates. The homology of the amino acid sequences of the peptides encoded by the two operons is extremely high but the intergenic regions share no related sequences. The expression of both the narGHJI operon and the narK gene are positively regulated by two transacting factors Fnr and NarL-Phosphate, activated respectively by anaerobiosis and nitrate, while the narZYWV operon and the narU gene are constitutively expressed. Nitrate reductase A, which accounts for 98% of the nitrate reductase activity when fully induced, is clearly the major respiratory nitrate reductase in E. coli while the physiological role of the constitutively expressed nitrate reductase Z remains to be defined. |
Mendeley readers
The data shown below were compiled from readership statistics for 63 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United Kingdom | 1 | 2% |
| United States | 1 | 2% |
| France | 1 | 2% |
| Unknown | 60 | 95% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Bachelor | 15 | 24% |
| Student > Ph. D. Student | 10 | 16% |
| Student > Master | 9 | 14% |
| Student > Doctoral Student | 4 | 6% |
| Researcher | 4 | 6% |
| Other | 7 | 11% |
| Unknown | 14 | 22% |
| Readers by discipline | Count | As % |
|---|---|---|
| Biochemistry, Genetics and Molecular Biology | 19 | 30% |
| Agricultural and Biological Sciences | 15 | 24% |
| Engineering | 3 | 5% |
| Chemistry | 3 | 5% |
| Immunology and Microbiology | 3 | 5% |
| Other | 5 | 8% |
| Unknown | 15 | 24% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 11 May 2021.
All research outputs
#8,534,528
of 25,371,288 outputs
Outputs from Antonie van Leeuwenhoek
#601
of 2,151 outputs
Outputs of similar age
#6,466
of 21,133 outputs
Outputs of similar age from Antonie van Leeuwenhoek
#3
of 5 outputs
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