Linked Life Data

21053918

Source:http://linkedlifedata.com/resource/pubmed/id/21053918

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
2010-12-1
pubmed:abstractText
The composition, stoichiometry, and organization of protein complexes can be determined by collision-induced dissociation (CID) coupled to tandem mass spectrometry (MS/MS). The increased use of this approach in structural biology prompts a better understanding of the dissociation mechanism(s). Here we report a detailed investigation of the CID of two dodecameric, heat-stable and toroidally shaped complexes: heat shock protein 16.9 (HSP16.9) and stable protein 1 (SP-1). While HSP16.9 dissociates by sequential loss of unfolded monomers, SP-1 ejects not only monomers, but also its building blocks (dimers), and multiples thereof (tetramers and hexamers). Unexpectedly, the dissociation of SP-1 is strongly charge-dependent: loss of the building blocks increases with higher charge states of this complex. By combining MS/MS with ion mobility (IM-MS/MS), we have monitored the unfolding and dissociation events for these complexes in the gas phase. For HSP16.9 unfolding occurs at lower energies than the ejection of subunits, whereas for SP-1 unfolding and dissociation take place simultaneously. We consider these results in the light of the structural organization of HSP16.9 and SP-1 and hypothesize that SP-1 is unable to unfold extensively due to its particular quaternary structure and unusually high charge density. This investigation increases our understanding of the factors governing the CID of protein complexes and moves us closer to the goal of obtaining structural information on subunit interactions and packing from gas-phase experiments.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1520-6882
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9702-10
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Ion mobility-mass spectrometry reveals the influence of subunit packing and charge on the dissociation of multiprotein complexes.
pubmed:affiliation
University Chemistry Department, University of Cambridge, Cambridge, United Kingdom.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't