Linked Life Data

2021632

Source:http://linkedlifedata.com/resource/pubmed/id/2021632

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1991-6-6
pubmed:abstractText
The microsomal triglyceride-transfer protein (MTP), which catalyzes the transport of triglyceride and cholesteryl ester between membranes, is a complex composed of two proteins having apparent molecular weights of 58,000 and 88,000. The 58,000 molecular weight component of MTP has been identified as the multifunctional protein, protein disulfide isomerase (PDI). The multisubunit nature of MTP as well as the presence of PDI as one of the subunits distinguishes this protein from previously characterized lipid-transfer proteins. In this study, we have more clearly defined structural elements of MTP that may play important functional roles. The molecular weight of the transfer protein complex was determined to be 150,000 by sedimentation equilibrium experiments performed at three different speeds, suggesting that MTP is a complex of one PDI and one 88,000 molecular weight polypeptide (88K). Following SDS-polyacrylamide gel electrophoresis, the Coomassie Blue staining intensity of PDI in a known amount of MTP was compared to that of known amounts of a PDI standard. A 1 to 0.98-1.30 ratio of PDI to 88K was determined, confirming the 1:1 stoichiometry of MTP. The sedimentation coefficient (5.85) determined by analytical ultracentrifugation and the Stokes radius (47 A) determined by polyacrylamide gradient gel electrophoresis indicate that the 150,000 molecular weight MTP complex is asymmetric and/or has an unusually high water of hydration. PDI and 88K form a stable protein complex; there was no evidence of a dissociation-reassociation reaction occurring between the two components. Analysis of far-ultraviolet circular dichroism spectra revealed MTP has about 28% alpha-helical and 28% beta-structural content.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4406-12
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Structural properties of the microsomal triglyceride-transfer protein complex.
pubmed:affiliation
Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Ohio 45267-0575.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't