| dc.contributor |
Wichita State University. Department of Chemistry |
en_US |
| dc.contributor.author |
Wimalasena, Kandatege |
en_US |
| dc.contributor.author |
Wimalasena, D. Shyamali |
en_US |
| dc.date.accessioned |
2012-02-06T17:16:59Z |
|
| dc.date.available |
2012-02-06T17:16:59Z |
|
| dc.date.issued |
1991-09-02 |
en_US |
| dc.identifier |
1785690 |
en_US |
| dc.identifier |
0370535 |
en_US |
| dc.identifier.citation |
Analytical biochemistry. 1991 Sep 2; 197(2): 353-61. |
en_US |
| dc.identifier.issn |
0003-2697 |
en_US |
| dc.identifier.uri |
http://hdl.handle.net/10057/4375 |
|
| dc.description |
Full text of this article is not available in SOAR. |
en_US |
| dc.description.abstract |
Based on the novel chromophoric electron donors, N,N-dimethyl-1,4-phenylenediamine (DMPD) and 2-amino-2-deoxy-L-ascorbic acid (2-aminoascorbic acid), two sensitive, convenient, and continuous spectrophotometric assays for dopamine beta-monooxygenase (EC 1.14.17.1) are described. Both, DMPD and 2-aminoascorbic acid are kinetically and stoichiometrically well-behaved electron donors for dopamine beta-monooxygenase with kinetic parameters comparable to the most efficient physiological electron donor, ascorbic acid. During dopamine beta-monooxygenase turnover, DMPD is converted to its chromophoric cation radical which is stable under the standard assay conditions. The rate of the enzyme-dependent formation of DMPD cation radical under standard assay conditions could easily be followed at 515 nm with high accuracy and reproducibility. Similarly, dopamine beta-monooxygenase-mediated oxidation of 2-aminoascorbic acid results in the formation of the known, stable chromophoric product, 2,2'-nitrilodi-2(2')-deoxy-L-ascorbic acid (red pigment), which has a very strong absorption maximum at 385 nm. Both the above assays are superior to the existing assays in their convenience, reproducibility, and sensitivity for routine kinetic analysis of dopamine beta-monooxygenase and may be adopted as a simple color test for the enzyme. We propose that the above assays could also be adopted to design continuous and sensitive spectrophotometric assays for ascorbate oxidase, peptidyl alpha-amidating monooxygenase, and the chromaffin granule electron transport protein, cytochrome b561, due to their remarkable similarity to dopamine beta-monooxygenase in the chemistry of catalysis with regard to the electron donor. |
en_US |
| dc.format.extent |
353-61 |
en_US |
| dc.language.iso |
eng |
en_US |
| dc.publisher |
Elsevier |
en_US |
| dc.relation.ispartofseries |
Analytical biochemistry |
en_US |
| dc.relation.ispartofseries |
Anal. Biochem. |
en_US |
| dc.source |
NLM |
en_US |
| dc.subject |
Research Support, Non-U.S. Gov't |
en_US |
| dc.subject.lcsh |
Ascorbic Acid/chemistry |
en_US |
| dc.subject.mesh |
Animals |
en_US |
| dc.subject.mesh |
Ascorbic Acid/analogs & derivatives |
en_US |
| dc.subject.mesh |
Cattle |
en_US |
| dc.subject.mesh |
Chemistry, Clinical |
en_US |
| dc.subject.mesh |
Chromaffin Granules/enzymology |
en_US |
| dc.subject.mesh |
Dopamine beta-Hydroxylase/analysis |
en_US |
| dc.subject.mesh |
Kinetics |
en_US |
| dc.subject.mesh |
Oxidation-Reduction |
en_US |
| dc.subject.mesh |
Phenylenediamines/chemistry |
en_US |
| dc.subject.mesh |
Spectrophotometry/methods |
en_US |
| dc.title |
Continuous spectrophotometric assays for dopamine beta-monooxygenase based on two novel electron donors: N,N-dimethyl-1,4-phenylenediamine and 2-aminoascorbic acid |
en_US |
| dc.type |
Article |
en_US |
| dc.coverage.spacial |
United States |
en_US |
| dc.description.version |
peer reviewed |
en_US |
| dc.rights.holder |
Copyright © 1991, Elsevier |
en_US |