Linked Life Data

1336460

Source:http://linkedlifedata.com/resource/pubmed/id/1336460

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1993-2-18
pubmed:abstractText
The structures of human carbonic-anhydrase-II complexes with the anionic inhibitors hydrogen sulphide (HS-) and nitrate (NO3-) have been determined by X-ray diffraction at 0.19-nm resolution from crystals soaked at pH 7.8 and 6.0, respectively. The modes of binding of these two anions differ markedly from each other. The strong inhibitor HS- replaces the native zinc-bound water/hydroxide (Wat263) leaving the tetrahedral metal geometry unaltered and acts as a hydrogen-bonding donor towards Thr199 gamma. The weak NO3- inhibitor does not displace Wat263 from the metal coordination but occupies a fifth binding site changing the zinc coordination polyhedron into a slightly distorted trigonal bipyramid. The interaction of NO3- with the metal is weak; the nearest of its oxygen atoms being at a distance of 0.28 nm from the zinc ion. The binding of nitrate to the enzyme is completed by a hydrogen bond to the metal coordinated Wat263 and a second one to a water molecule of the active-site cavity. The structures of the two complexes help to rationalize the binding of anionic inhibitors to carbonic anhydrase and the binding mode displayed by NO39 may be relevant to the catalytic mechanism.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
210
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
867-71
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Crystallographic studies of the binding of protonated and unprotonated inhibitors to carbonic anhydrase using hydrogen sulphide and nitrate anions.
pubmed:affiliation
Chemistry Department, University of Siena, Italy.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't