Linked Life Data

8780775

Source:http://linkedlifedata.com/resource/pubmed/id/8780775

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1996-10-24
pubmed:abstractText
GroEL and DnaK with their cofactors constitute the major chaperone systems promoting protein folding in the Escherichia coli cytosol. The ability of GroEL to bind and promote folding of a substrate released from DnaK led to the proposal that the DnaK and GroEL systems act successively along a protein folding pathway. Here we have investigated the role of both systems in preventing aggregation and assisting refolding of firefly luciferase denatured by guanidinium chloride and heat. We find that DnaK and GroEL compete with each other for binding to non-native luciferase. Addition of ATP and co-operating proteins results in release of luciferase from either chaperone in a non-native conformation. Only a small fraction of luciferase molecules released from GroEL can reach the native state. Instead, the released luciferase must bind repeatedly to the DnaK system, and only then is it able to fold to the native state. Thus, during a folding reaction, DnaK and GroEL do not obligatorily act in succession by promoting earlier and later protein folding steps, respectively. Rather, the two chaperone systems and perhaps others can form a lateral network of co-operating proteins. This chaperone network is proposed to be of particular importance for the assisted refolding of proteins that are unfolded by stress treatment such as heat shock and whose size is too large to allow folding inside the substrate binding cavity of the GroEL ring underneath GroES.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
261
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
328-33
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Substrate shuttling between the DnaK and GroEL systems indicates a chaperone network promoting protein folding.
pubmed:affiliation
Zentrum für Molekulare Biologie, Universität Heidelberg, FRG.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't