Linked Life Data

9622483

Source:http://linkedlifedata.com/resource/pubmed/id/9622483

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
1998-6-30
pubmed:databankReference
pubmed:abstractText
Adenosine deaminase, which catalyzes the irreversible hydrolytic deamination of adenosine nucleosides to inosine nucleosides and ammonia, is a key enzyme in purine metabolism and lymphoid development. The X-ray structures of murine adenosine deaminase with bound potent inhibitors (Ki values approximately 10(-13) M) (8R)-hydroxyl-2'-deoxycoformycin (pentostatin), a transition state analogue, and (6S)-hydroxyl-1,6-dihydropurine riboside, a reaction coordinate analogue, have been determined and refined to resolutions of 2.6 and 1.95 A, respectively. Crystals of both complexes were obtained at pH 7, where the enzyme is fully active, in an identical space group with the asymmetric unit containing four molecules. In addition to the very high degree of similarity between the four independent molecules in each complex structure, there is also considerable structural similarity of the complex with the dihydropurine riboside with that of an identical complex previously determined at pH 4.2 where the enzyme is 20% active. The interactions between the enzyme and the two analogues are extremely similar. These include the coordination of the 8R- or 6S-hydroxyl group of the analogues to the Zn2+ which mainly contributes to the strong potency and very high degree of stereospecificity of inhibition by these analogues. The interactions are further indicative of the structural and chemical requirements of substrates. These structures and recent site-directed mutagenesis have further shed light on the catalytic mechanism of the enzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8314-24
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Complexes of adenosine deaminase with two potent inhibitors: X-ray structures in four independent molecules at pH of maximum activity.
pubmed:affiliation
Structural and Computational Biology and Molecular Biophysics Program, Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas 77030, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't