Linked Life Data

19824612

Source:http://linkedlifedata.com/resource/pubmed/id/19824612

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
45
pubmed:dateCreated
2009-11-10
pubmed:abstractText
Protein synthesis is a highly conserved process in all living cells involving several members of the translation factor (TRAFAC) class of P-loop GTPases, which play essential roles during translation. The universally conserved GTPase HflX has previously been shown to associate with the 50S ribosomal subunit, as well as to bind and hydrolyze both GTP and ATP. In an effort to elucidate the cellular function of HflX, we have determined the kinetic parameters governing the interaction between HflX and these two purine nucleotides using fluorescence-based steady-state and pre-steady-state techniques. On the basis of these, we demonstrate that the GTPase and ATPase activity of HflX is stimulated by 50S and 70S ribosomal particles. However, given cellular concentrations of the two purine nucleotides, approximately 80% of HflX will be bound to guanine nucleotides, indicating that HflX may function as a guanine nucleotide dependent enzyme in vivo. Using a highly purified reconstituted in vitro translation system, we show that the GTPase activity of HflX is also stimulated by poly(U) programmed 70S ribosomes and that the ribosome-dependent GTPase stimulation is specifically inhibited by the antibiotic chloramphenicol, which binds to the large ribosomal subunit, but not by kanamycin, an aminoglycoside targeting the small ribosomal subunit.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1520-4995
pubmed:author
pubmed:issnType
Electronic
pubmed:day
17
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10793-802
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Toward understanding the function of the universally conserved GTPase HflX from Escherichia coli: a kinetic approach.
pubmed:affiliation
Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, Alberta, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't