Linked Life Data

9874254

Source:http://linkedlifedata.com/resource/pubmed/id/9874254

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-1-28
pubmed:databankReference
pubmed:abstractText
The archaeon Pyrodictium occultum is one of the most thermophilic organisms presently known. Previous experiments provided support for the significant contribution of a high-molecular-mass protein complex to the extreme thermotolerance of P. occultum. This protein complex, the 'thermosome', is composed of two subunits, alpha and beta, which form a hexadecameric double ring complex. In order to obtain the thermosome in amounts sufficient for structural and functional investigations, we produced the two subunits jointly and separately in Escherichia coli BL21(DE3). In all three cases, we isolated soluble, high-molecular-mass double-ring complexes from E. coli BL21(DE3). On electron micrographs, the recombinant complexes were indistinguishable from each other and from the natural thermosome. To characterize the quaternary structure of the recombinant particles, we used native gel electrophoresis, analytical gel filtration, and analytical ultracentrifugation. Spectral analysis, using absorption, fluorescence emission and far-UV circular dichroism spectroscopy were applied to compare the three recombinant protein complexes with the natural thermosome from P. occultum. All three recombinant complex species exhibit ATPase activity. Furthermore, we could demonstrate that the recombinant complexes slow down the aggregation of citrate synthase, alcohol dehydrogenase, and insulin. Thus, we conclude that the recombinant protein complexes exhibit a chaperone-like activity, interacting with non-native proteins; they do so at temperatures far below the lower physiological limit of growth.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
258
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
837-45
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Recombinant homo- and hetero-oligomers of an ultrastable chaperonin from the archaeon Pyrodictium occultum show chaperone activity in vitro.
pubmed:affiliation
Institut für Biophysik und physikalische Biochemie, Universität Regensburg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't