text

Continuous spectrophotometric assays for dopamine beta-monooxygenase based on two novel electron donors: N,N-dimethyl-1,4-phenylenediamine and 2-aminoascorbic acid

SOAR Repository

Show simple item record

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

Files in this item

Files Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record

Search SOAR


Advanced Search

Browse

My Account

Statistics