Linked Life Data

18942851

Source:http://linkedlifedata.com/resource/pubmed/id/18942851

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
46
pubmed:dateCreated
2008-11-12
pubmed:abstractText
We have investigated the temperature-dependent interaction of the porins OmpF from Paracoccus denitrificans and OmpG from Escherichia coli with lipid molecules after reconstitution in lecithin. Effects of incubation at increased temperatures on activity were tested by functional experiments for OmpG and compared with previously published results of OmpF in order to understand the activity loss of OmpF with monomerization. Protein-lipid interaction was monitored by different reporter groups both from lipid molecules and from protein. OmpF loses its activity by approximately 90% at 50 degrees C while OmpG does not show a temperature-dependent change in activity between room temperature and 50 degrees C. The interaction between OmpF and lipid molecules is severely altered in a two-step mechanism at 55 and approximately 75 degrees C for OmpF. The first step is attributed to changes in the degree of interaction between the aromatic girdle of OmpF and the interfacial region of the lipid bilayer, leading to monomerization of this trimeric porin. The second step at 75 degrees C is attributed to the changes in lipid-porin monomer interaction. Around 90 degrees C, reconstituted porin aggregates. For OmpG, changes in lipid-protein interaction were observed starting from approximately 80 degrees C because of temperature-induced breakdown of its folding. This study provides deeper understanding of porin-lipid bilayer interaction as a function of temperature and can explain the functional breakdown by monomerization while porin secondary structure is still preserved.
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
18
pubmed:volume
47
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12126-34
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
The role of lipids for the functional integrity of porin: an FTIR study using lipid and protein reporter groups.
pubmed:affiliation
Institute of Biophysics, Johann Wolfgang Goethe-University, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't