Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
1995-8-17
pubmed:abstractText
A series of competitive inhibitors of carbonic anhydrase II (CAII; EC 4.2.1.1) that consists of oligo(ethylene glycol) units attached to p-benzenesulfonamides with pendant amino acids, H2NSO2C6H4CONHCH2CH2OCH2CH2OCH2CH2NHCOCHRNH3+, have been synthesized and examined using competitive fluorescence assays. Three of the strongest inhibitors, designated EG3NH3+, EG3GlyNH3+, and EG3PheNH3+, have been studied by X-ray crystallographic methods at limiting resolutions of 1.9, 2.0, and 2.3 A, respectively. The sulfonamide-zinc binding modes and the association of the ethylene glycol linkers to the hydrophobic patch of the active site are similar in all three inhibitors. Differences in the values of Kd are therefore not due to differences in zinc coordination or to differences in the modes of enzyme-glycol association but instead appear to arise from interaction of the pendant amino acids with the surface of the protein. These pendant groups are, however, not sufficiently ordered to be visible in electron density maps. Thus, structural variations of inhibitors at locations distant from the primary binding (i.e., the sulfonamide group) site affect the overall binding affinities of inhibitors (e.g., Kd (EG3PheNH3+) = 14 nM as compared with Kd (EG3GluNH3+) = 100 nM).
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2286-91
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Secondary interactions significantly removed from the sulfonamide binding pocket of carbonic anhydrase II influence inhibitor binding constants.
pubmed:affiliation
Department of Chemistry, University of Pennsylvania, Philadelphia 19104-6323, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.