Linked Life Data

16306996

Source:http://linkedlifedata.com/resource/pubmed/id/16306996

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7067
pubmed:dateCreated
2005-11-24
pubmed:databankReference
pubmed:abstractText
The large ribosomal subunit catalyses the reaction between the alpha-amino group of the aminoacyl-tRNA bound to the A site and the ester carbon of the peptidyl-tRNA bound to the P site, while preventing the nucleophilic attack of water on the ester, which would lead to unprogrammed deacylation of the peptidyl-tRNA. Here we describe three new structures of the large ribosomal subunit of Haloarcula marismortui (Hma) complexed with peptidyl transferase substrate analogues that reveal an induced-fit mechanism in which substrates and active-site residues reposition to allow the peptidyl transferase reaction. Proper binding of an aminoacyl-tRNA analogue to the A site induces specific movements of 23S rRNA nucleotides 2618-2620 (Escherichia coli numbering 2583-2585) and 2541(2506), thereby reorienting the ester group of the peptidyl-tRNA and making it accessible for attack. In the absence of the appropriate A-site substrate, the peptidyl transferase centre positions the ester link of the peptidyl-tRNA in a conformation that precludes the catalysed nucleophilic attack by water. Protein release factors may also function, in part, by inducing an active-site rearrangement similar to that produced by the A-site aminoacyl-tRNA, allowing the carbonyl group and water to be positioned for hydrolysis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1476-4687
pubmed:author
pubmed:issnType
Electronic
pubmed:day
24
pubmed:volume
438
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
520-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
An induced-fit mechanism to promote peptide bond formation and exclude hydrolysis of peptidyl-tRNA.
pubmed:affiliation
Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, N.I.H., Extramural