Linked Life Data

9333323

Source:http://linkedlifedata.com/resource/pubmed/id/9333323

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
37
pubmed:dateCreated
1997-10-14
pubmed:databankReference
pubmed:abstractText
Activation of gluatmine phosphoribosylpyrophosphate (RPPP) amidotransferase (GPATase) by binding of a PRPP substrate analog results in the formation of a 20 A channel connecting the active site for glutamine hydrolysis in one domain with the PRPP site in a second domain. This solvent-inaccessible channel permits transfer of the NH3 intermediate between the two active sites. Tunneling of NH3 may be a common mechanism for glutamine amidotransferase-catalyzed nitrogen transfer and for coordination of catalysis at two distinct active sites in complex enzymes. The 2.4 A crystal structure of the active conformer of GPATase also provides the first description of an intact active site for the phosphoribosyltransferase (PRTase) family of nucleotide synthesis and salvage enzymes. Chemical assistance to catalysis is provided primarily by the substrate and secondarily by the enzyme in the proposed structure-based mechanism. Different catalytic and inhibitory modes of divalent cation binding to the PRTase active site are revealed in the active conformer of the enzyme and in a feedback-inhibited GMP complex.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11061-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Coupled formation of an amidotransferase interdomain ammonia channel and a phosphoribosyltransferase active site.
pubmed:affiliation
Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't