Linked Life Data

18342970

Source:http://linkedlifedata.com/resource/pubmed/id/18342970

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3-4
pubmed:dateCreated
2008-4-8
pubmed:abstractText
Mutants of transketolase (TK) with improved substrate specificity towards the non-natural aliphatic aldehyde substrate propionaldehyde have been obtained by directed evolution. We used the same active-site targeted saturation mutagenesis libraries from which we previously identified mutants with improved activity towards glycolaldehyde, which is C2-hydroxylated like all natural TK substrates. Comparison of the new mutants to those obtained previously reveals distinctly different subsets of enzyme active-site mutations with either improved overall enzyme activity, or improved specificity towards either the C2-hydroxylated or non-natural aliphatic aldehyde substrate. While mutation of phylogenetically variant residues was found previously to yield improved enzyme activity on glycolaldehyde, we show here that these mutants in fact gave improved activity on both substrate types. In comparison, the new mutants were obtained at conserved residues which interact with the C2-hydroxyl group of natural substrates, and gave up to 5-fold improvement in specific activity and 64-fold improvement in specificity towards propionaldehyde relative to glycolaldehyde. This suggests that saturation mutagenesis can be more selectively guided for evolution towards either natural or non-natural substrates, using both structural and sequence information.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0168-1656
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
134
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
240-5
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Directed evolution of transketolase substrate specificity towards an aliphatic aldehyde.
pubmed:affiliation
Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't