Linked Life Data

3663592

Source:http://linkedlifedata.com/resource/pubmed/id/3663592

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
1987-12-7
pubmed:abstractText
The interactions of the targeting sequence of the mitochondrial enzyme ornithine transcarbamylase with phospholipid bilayers of different molecular compositions have been studied by high-sensitivity heating and cooling differential scanning calorimetry, high-sensitivity isothermal titration calorimetry, fluorescence spectroscopy, and electron microscopy. These studies indicate that the leader peptide interacts strongly with dipalmitoylphosphatidylcholine (DPPC) bilayer membranes containing small mole percents of the anionic phospholipids dipalmitoylphosphatidylglycerol (DPPG) or brain phosphatidylserine (brain PS) but not with pure phosphatidylcholines. For the first time, the energetics of the leader peptide-membrane interaction have been measured directly by using calorimetric techniques. At 20 degrees C, the association of the peptide with the membrane is exothermic and characterized by an association constant of 2.3 X 10(6) M-1 in the case of phosphatidylglycerol-containing and 0.35 X 10(6) M-1 in the case of phosphatidylserine-containing phospholipid bilayers. In both cases, the enthalpy of association is -60 kcal/mol of peptide. Additional experiments using fluorescence techniques suggest that the peptide does not penetrate deeply into the hydrophobic core of the membrane. The addition of the leader peptide to DPPC/DPPG (5:1) or DPPC/brain PS (5:1) small sonicated vesicles results in vesicle fusion. The fusion process is dependent on peptide concentration and is maximal at the phase transition temperature of the vesicles and minimal at temperatures below the phase transition.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4309-15
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Thermodynamic characterization of interactions between ornithine transcarbamylase leader peptide and phospholipid bilayer membranes.
pubmed:affiliation
Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.