Linked Life Data

10747936

Source:http://linkedlifedata.com/resource/pubmed/id/10747936

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
2000-8-10
pubmed:databankReference
pubmed:abstractText
The crystal structure is reported at 1.8 A resolution of Escherichia coli ornithine transcarbamoylase in complex with the active derivative of phaseolotoxin from Pseudomonas syringae pv. phaseolicola, N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine. Electron density reveals that the complex is not a covalent adduct as previously thought. Kinetic data confirm that N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine exhibits reversible inhibition with a half-life in the order of approximately 22 h and a dissociation constant of K(D) = 1.6 x 10(-12) m at 37 degrees C and pH 8.0. Observed hydrogen bonding about the chiral tetrahedral phosphorus of the inhibitor is consistent only with the presence of the R enantiomer. A strong interaction is also observed between Arg(57) Nepsilon and the P-N-S bridging nitrogen indicating that imino tautomers of N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine are present in the bound state. An imino tautomer of N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine is structurally analogous to the proposed reaction transition state. Hence, we propose that N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine, with its three unique N-P bonds, represents a true transition state analogue for ornithine transcarbamoylases, consistent with the tight binding kinetics observed.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
20012-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Mechanism of inactivation of ornithine transcarbamoylase by Ndelta -(N'-Sulfodiaminophosphinyl)-L-ornithine, a true transition state analogue? Crystal structure and implications for catalytic mechanism.
pubmed:affiliation
Department of Biochemistry, The University of Sydney, Sydney 2006, Australia and the Horticultural and Food Research Institute of New Zealand, Mt Albert Research Centre, Auckland 1003, New Zealand.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't