Linked Life Data

4074695

Source:http://linkedlifedata.com/resource/pubmed/id/4074695

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1986-2-7
pubmed:abstractText
An improved procedure is described for the isolation of the flavocytochrome p-cresol methylhydroxylase (PCMH) from Pseudomonas putida as well as methods for the separation of its subunits in native form and their recombination to reconstitute the original flavocytochrome. Under appropriate conditions, the reconstitution is stoichiometric and results in complete recovery of the catalytic activity of the flavocytochrome. The separated flavoprotein subunit shows only 2% of the catalytic activity of the original enzyme on p-cresol and is characterized by converging lines in bisubstrate kinetic analysis, while the intact and reconstituted enzymes show parallel line kinetics in steady-state experiments. van't Hoff plots of the dependence of the dissociation constant of the subunits of PCMH on temperature show a break near 15 degrees C. Above this temperature, KD is characterized by a positive delta H value of 12.6 kcal mol-1; below 15 degrees C, the dissociation is essentially temperature independent. The subunit dissociation is strongly dependent on ionic strength in the oxidized form of PCMH but not in the reduced form of the enzyme. Reduction also lowers the KD significantly, while substrates and nonoxidizable competitive inhibitors lower the dissociation constant even further, suggesting a conformation change. Combination of the subunits to form PCMH entails a small but measurable change in the absorption spectra of the component proteins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5276-80
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Resolution of the flavocytochrome p-cresol methylhydroxylase into subunits and reconstitution of the enzyme.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.