Linked Life Data

17317664

Source:http://linkedlifedata.com/resource/pubmed/id/17317664

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
2007-4-9
pubmed:abstractText
SspB is a dimeric adaptor protein that increases the rate at which ssrA-tagged substrates are degraded by tethering them to the ClpXP protease. Each SspB subunit consists of a folded domain that forms the dimer interface and a flexible C-terminal tail. Ternary delivery complexes are stabilized by three sets of tethering interactions. The C-terminal XB peptide of each SspB subunit binds ClpX, the body of SspB binds one part of the ssrA-tag sequence, and ClpX binds another part of the tag. To test the functional importance of these tethering interactions, we engineered monomeric SspB variants and dimeric variants with different length linkers between the SspB body and the XB peptide and employed substrates with degradation tags that bind ClpX weakly and/or contain extensions between the binding sites for SspB and ClpX. We find that monomeric SspB variants can enhance ClpXP degradation of a subset of substrates, that doubling the number of tethering interactions stimulates degradation via changes in Km and Vmax, and that major alterations in the length of the 48-residue SspB linker cause only small changes in the efficiency of substrate delivery. These results indicate that the properties of the degradation tag and the number of SspB.ClpX tethering interactions are the major factors that determine the extent to which the substrate and ClpX are engaged in ternary delivery complexes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
282
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11465-73
pubmed:dateRevised
2011-1-25
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Altered tethering of the SspB adaptor to the ClpXP protease causes changes in substrate delivery.
pubmed:affiliation
Department of Biology and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural