Linked Life Data

3927983

Source:http://linkedlifedata.com/resource/pubmed/id/3927983

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1985-10-18
pubmed:abstractText
Apolipoprotein A-I, the major structural polypeptide of human high-density lipoproteins, activates lecithin: cholesterol acyltransferase, the cholesterol ester-forming enzyme in plasma. Apolipoprotein A-I, like several other apolipoproteins, exhibits structural adaptability, which is manifest in a low free energy of stabilization and facile changes in secondary structure. We have investigated the dual effects of guanidinium chloride (GdmCl) and pressure perturbation at low GdmCl concentrations on apolipoproteins A-I conformational states, using fluorescence detection. Pressure alone (up to 3 kilobar) is insufficient to fully denature apolipoprotein A-I, and results in formation of metastable state(s). However, in conjunction with low concentrations of GdmCl the calculated volume change upon pressure denaturation increases from approx. -50 ml/mol to -90 ml/mol. The free energy of denaturation by pressure perturbation ranges from 1.4 to 1.8 kcal/mol, but the conformational states induced by pressure and GdmCl perturbation are most likely different. The physico-chemical properties of native and pressure-denatured conformational states can be, readily and reversibly, measured by fluorescence techniques. Biological activity of apolipoprotein A-I in the form of lecithin: cholesterol acyltransferase activation, is also reversible upon pressure perturbation. Samples of apolipoprotein A-I exposed to 2 kbar for an hour activated lecithin: cholesterol acyltransferase equally well as controls. To delineate more precisely the conformational states of apolipoprotein A-I under pressure, time-dependent anisotropy decay measurements, capable of resolving rotational heterogeneity, will be required.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
836
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
215-21
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Reversible folding reactions of human apolipoprotein A-I: pressure and guanidinium chloride effects.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.