Linked Life Data

10199659

Source:http://linkedlifedata.com/resource/pubmed/id/10199659

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1999-6-1
pubmed:abstractText
Four-helix bundle proteins have been designed that catalyze the hydrolysis and transesterification reactions of p-nitrophenyl esters by a cooperative nucleophilic and general acid mechanism. The catalysts consist of two 42-residue peptides that fold into helix-loop-helix motifs and dimerise. They have previously been shown to recognize anionic and hydrophobic substrates and to follow saturation kinetics. The catalytic entity is a HisH(+)-His pair in a helical segment spaced i, i+4, which can be supplemented by arginines and lysines in the adjacent helix. The binding residues have now been optimized for the catalysis of mono-p-nitrophenyl fumarate hydrolysis and found to vary with the location of the site. The catalytic efficiency of the HisH(+)-His site in helix II in positions 30 and 34 is enhanced by the introduction of arginine and or lysine residues in positions 11 and 15, but not in 8 and 11 or in 15 and 19. The most efficient catalyst using this site, JNIIR11K15, catalyses the reaction with a second-order rate constant of 0.134 M(-1) s(-1) in aqueous solution at pH 5.1 and 290 K. The second-order rate constant is larger than those of the corresponding sites with 'longer' and 'shorter' binding residues. Similar experiments have shown that the efficiency and selectivity of catalysts based on a HisH(+)-11-His-15 site in helix I are enhanced the most by the introduction of Lys-30 and Arg-34.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0968-0896
pubmed:author
pubmed:issnType
Print
pubmed:volume
7
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
83-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10199659-Amino Acid Sequence, pubmed-meshheading:10199659-Arginine, pubmed-meshheading:10199659-Binding Sites, pubmed-meshheading:10199659-Catalysis, pubmed-meshheading:10199659-Esterification, pubmed-meshheading:10199659-Esters, pubmed-meshheading:10199659-Fumarates, pubmed-meshheading:10199659-Helix-Loop-Helix Motifs, pubmed-meshheading:10199659-Histidine, pubmed-meshheading:10199659-Hydrolysis, pubmed-meshheading:10199659-Kinetics, pubmed-meshheading:10199659-Lysine, pubmed-meshheading:10199659-Models, Molecular, pubmed-meshheading:10199659-Molecular Sequence Data, pubmed-meshheading:10199659-Nitrobenzenes, pubmed-meshheading:10199659-Peptides, pubmed-meshheading:10199659-Phenylacetates, pubmed-meshheading:10199659-Protein Binding, pubmed-meshheading:10199659-Protein Folding, pubmed-meshheading:10199659-Protein Structure, Secondary, pubmed-meshheading:10199659-Proteins
pubmed:year
1999
pubmed:articleTitle
Designed four-helix bundle catalysts--the engineering of reactive sites for hydrolysis and transesterification reactions of p-nitrophenyl esters.
pubmed:affiliation
Department of Chemistry, Göteborg University, Sweden. lars.baltzer@oc.chalmers.se
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't