Linked Life Data

18502765

Source:http://linkedlifedata.com/resource/pubmed/id/18502765

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
30
pubmed:dateCreated
2008-7-21
pubmed:databankReference
pubmed:abstractText
The coding sequence of the cyanobacterium Synechocystis sp. strain PCC 6803 slr0095 gene was cloned and functionally expressed in Escherichia coli. The corresponding enzyme was classified as a cation- and S-adenosyl-l-methionine-dependent O-methyltransferase (SynOMT), consistent with considerable amino acid sequence identities to eukaryotic O-methyltransferases (OMTs). The substrate specificity of SynOMT was similar with those of plant and mammalian CCoAOMT-like proteins accepting a variety of hydroxycinnamic acids and flavonoids as substrates. In contrast to the known mammalian and plant enzymes, which exclusively methylate the meta-hydroxyl position of aromatic di- and trihydroxy systems, Syn-OMT also methylates the para-position of hydroxycinnamic acids like 5-hydroxyferulic and 3,4,5-trihydroxycinnamic acid, resulting in the formation of novel compounds. The x-ray structure of SynOMT indicates that the active site allows for two alternative orientations of the hydroxylated substrates in comparison to the active sites of animal and plant enzymes, consistent with the observed preferred para-methylation and position promiscuity. Lys(3) close to the N terminus of the recombinant protein appears to play a key role in the activity of the enzyme. The possible implications of these results with respect to modifications of precursors of polymers like lignin are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
283
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
20888-96
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Functional and structural characterization of a cation-dependent O-methyltransferase from the cyanobacterium Synechocystis sp. strain PCC 6803.
pubmed:affiliation
Department of Physical Biotechnology, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale) 06099, Germany.
pubmed:publicationType
Journal Article