Linked Life Data

16023070

Source:http://linkedlifedata.com/resource/pubmed/id/16023070

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-8-1
pubmed:abstractText
A cDNA was cloned from Ruta graveolens cells encoding a novel O-methyltransferase (OMT) with high similarity to orcinol or chavicol/eugenol OMTs, but containing a serine-rich N-terminus and a 13 amino acid insertion between motifs IV and V. Expression in Escherichia coli revealed S-adenosyl-l-methionine-dependent OMT activity with methoxylated phenols only with an apparent Km of 20.4 for the prime substrate 3,5-dimethoxyphenol. The enzyme forms a homodimer of 84 kDa, and the activity was insignificantly affected by 2.0 mM Ca2+ or Mg2+, whereas Fe2+, Co2+, Zn2+, Cu2+ or Hg2+ were inhibitory (78-100%). Dithiothreitol (DTT) suppressed the OMT activity. This effect was examined further, and, in the presence of Zn2+ as a potential thiol methyltransferase (TMT) cofactor, the recombinant OMT methylated DTT to DTT-monomethylthioether. Sets of kinetic OMT experiments with 3,5-dimethoxyphenol at various Zn2+/DTT concentrations revealed the competitive binding of DTT with an apparent Ki of 52.0 microM. Thus, the OMT exhibited TMT activity with almost equivalent affinity to the thiol pseudosubstrate which is structurally unrelated to methoxyphenols.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
440
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
54-64
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Unusual pseudosubstrate specificity of a novel 3,5-dimethoxyphenol O-methyltransferase cloned from Ruta graveolens L.
pubmed:affiliation
Institut für Pharmazeutische Biologie, Philipps-Universität Marburg, Deutschhausstrasse 17A, D-35037 Marburg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't