Linked Life Data

18329375

Source:http://linkedlifedata.com/resource/pubmed/id/18329375

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2008-4-15
pubmed:abstractText
2-Nitropropane dioxygenase from Hansenula mrakii was expressed in Escherichia coli cells and purified in active and stable form using 60% saturation of ammonium sulfate and a single chromatographic step onto a DEAE column. MALDI-TOF mass spectrometric and spectrophotometric analyses of the flavin extracted by heat or acid denaturation of the enzyme indicated that FMN, and not FAD as erroneously reported previously, is present in a 1:1 stoichiometry with the protein. Inductively coupled plasma mass spectrometric analysis of the enzyme established that H. mrakii 2-nitropropane dioxygenase contains negligible amounts of iron, manganese, zinc, and copper ions, which are not catalytically relevant. Anaerobic substrate reduction and kinetic data using a Clark oxygen electrode to measure rates of oxygen consumption indicated that the enzyme is active on a broad range of alkyl nitronates, with a marked preference for unbranched substrates over propyl-2-nitronate. Interestingly, the enzyme reacts poorly, if at all, with nitroalkanes, as suggested by lack of both anaerobic reduction of the enzyme-bound flavin and consumption of oxygen with nitroethane, nitrobutane, and 2-nitropropane. Finally, both the tight binding of sulfite (K(d)=90 microM, at pH 8 and 15 degrees C) to the enzyme and the formation of the anionic flavosemiquinone upon anaerobic incubation with alkyl nitronates are consistent with the presence of a positively charged group in proximity of the N1-C2=O atoms of the FMN cofactor.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1096-0384
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
473
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
61-8
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Oxidation of alkyl nitronates catalyzed by 2-nitropropane dioxygenase from Hansenula mrakii.
pubmed:affiliation
Department of Chemistry, Georgia State University, P.O. Box 4098, Atlanta, GA 30302-4098, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't