Linked Life Data

2350178

Source:http://linkedlifedata.com/resource/pubmed/id/2350178

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-7-11
pubmed:abstractText
N-(2-Fluorophenyl)-N-phenylcarbamoyl chloride is shown to react with alpha-chymotrypsin to give a catalytically inactive material. A crystal structure determination shows that the chloride exists in the solid state in two conformations. In both of these the aromatic rings are tilted substantially relative to the plane through the atoms of the carbamoyl chloride group; the structures differ by a 180 degrees rotation of the 2-fluorophenyl ring. Fluorine NMR studies of alpha-chymotrypsin modified with this carbamoyl chloride show that, when bound to the enzyme, one aromatic ring of the diphenylcarbamoyl group likely rotates slowly while the other rotates much more rapidly or else is frozen in one dominant conformation. In the denatured enzyme (8 M urea) at room temperature and above, both aromatic rings of the diphenylcarbamoyl group appear to be rapidly rotating although differential linewidth changes observed at lower sample temperatures suggest that rotation of one ring becomes slow under these conditions. Rotation about the carbamoyl carbon-nitrogen bond is detected in fluorine NMR spectra of both the native and the denatured modified enzymes as the sample temperature is increased. Rates of carbamoyl rotation in the chloride, in the native modified enzyme, and in the denatured enzyme at 25 degrees C are approximately 66, 10, and 200 s-1, respectively.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
305-14
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Conformations of N-(2-fluorophenyl)-N-phenylcarbamoyl-alpha-chymotrypsin.
pubmed:affiliation
Department of Chemistry, University of Ioannina, Greece.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't