Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2006-9-18
pubmed:abstractText
Enzymes hydrolysing highly toxic organophosphate esters (OPs) are promising alternatives to pharmacological countermeasures against OPs poisoning. Bungarus fasciatus acetylcholinesterase (BfAChE) was engineered to acquire organophosphate hydrolase (OPase) activity by reproducing the features of the human butyrylcholinesterase G117H mutant, the first mutant designed to hydrolyse OPs. The modification consisted of a triple mutation on the (122)GFYS(125) peptide segment, resulting in (122)HFQT(125). This substitution introduced a nucleophilic histidine above the oxyanion hole, and made space in that region. The mutant did not show inhibition by excess acetylthiocholine up to 80 mM. The k(cat)/K(m) ratio with acetylthiocholine was 4 orders of magnitude lower than that of wild-type AChE. Interestingly, due to low affinity, the G122H/Y124Q/S125T mutant was resistant to sub-millimolar concentrations of OPs. Moreover, it had hydrolysing activity with paraoxon, echothiophate, and diisopropyl phosphofluoridate (DFP). DFP was characterised as a slow-binding substrate. This mutant is the first mutant of AChE capable of hydrolysing organophosphates. However, the overall OPase efficiency was greatly decreased compared to G117H butyrylcholinesterase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
1764
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1470-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Mutant of Bungarus fasciatus acetylcholinesterase with low affinity and low hydrolase activity toward organophosphorus esters.
pubmed:affiliation
Département de Toxicologie, Centre de Recherches du Service de Santé des Armées, BP 87, 38702 La Tronche Cedex, France. tpoyot@crssa.net
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't