| Title |
d-Amino acid dehydrogenase from Helicobacter pylori NCTC 11637
|
|---|---|
| Published in |
Amino Acids, February 2009
|
| DOI | 10.1007/s00726-009-0240-0 |
| Pubmed ID | |
| Authors |
Minoru Tanigawa, Tomomitsu Shinohara, Makoto Saito, Katsushi Nishimura, Yuichiro Hasegawa, Sadao Wakabayashi, Morio Ishizuka, Yoko Nagata |
| Abstract |
Helicobacter pylori is a microaerophilic bacterium, associated with gastric inflammation and peptic ulcers. D-Amino acid dehydrogenase is a flavoenzyme that digests free neutral D-amino acids yielding corresponding 2-oxo acids and hydrogen. We sequenced the H. pylori NCTC 11637 D-amino acid dehydrogenase gene, dadA. The primary structure deduced from the gene showed low similarity with other bacterial D-amino acid dehydrogenases. We purified the enzyme to homogeneity from recombinant Escherichia coli cells by cloning dadA. The recombinant protein, DadA, with 44 kDa molecular mass, possessed FAD as cofactor, and showed the highest activity to D-proline. The enzyme mediated electron transport from D-proline to coenzyme Q(1), thus distinguishing it from D-amino acid oxidase. The apparent K(m) and V(max) values were 40.2 mM and 25.0 micromol min(-1) mg(-1), respectively, for dehydrogenation of D-proline, and were 8.2 microM and 12.3 micromol min(-1) mg(-1), respectively, for reduction of Q(1). The respective pH and temperature optima were 8.0 and 37 degrees C. Enzyme activity was inhibited markedly by benzoate, and moderately by SH reagents. DadA showed more similarity with mammalian D-amino acid oxidase than other bacterial D-amino acid dehydrogenases in some enzymatic characteristics. Electron transport from D-proline to a c-type cytochrome was suggested spectrophotometrically. |
Mendeley readers
The data shown below were compiled from readership statistics for 17 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 1 | 6% |
| Unknown | 16 | 94% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 8 | 47% |
| Researcher | 3 | 18% |
| Student > Master | 2 | 12% |
| Student > Doctoral Student | 1 | 6% |
| Student > Bachelor | 1 | 6% |
| Other | 2 | 12% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 9 | 53% |
| Biochemistry, Genetics and Molecular Biology | 4 | 24% |
| Chemical Engineering | 1 | 6% |
| Immunology and Microbiology | 1 | 6% |
| Chemistry | 1 | 6% |
| Other | 0 | 0% |
| Unknown | 1 | 6% |
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 08 March 2015.
All research outputs
#7,454,951
of 22,790,780 outputs
Outputs from Amino Acids
#495
of 1,518 outputs
Outputs of similar age
#50,042
of 172,072 outputs
Outputs of similar age from Amino Acids
#8
of 12 outputs
Altmetric has tracked 22,790,780 research outputs across all sources so far. This one is in the 44th percentile – i.e., 44% of other outputs scored the same or lower than it.
So far Altmetric has tracked 1,518 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 6.7. This one is in the 41st percentile – i.e., 41% of its peers scored the same or lower than it.
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We're also able to compare this research output to 12 others from the same source and published within six weeks on either side of this one. This one is in the 1st percentile – i.e., 1% of its contemporaries scored the same or lower than it.