Linked Life Data

2350493

Source:http://linkedlifedata.com/resource/pubmed/id/2350493

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-7-19
pubmed:abstractText
At physiological pH and temperature, glucagon binds to liposomes composed of egg phosphatidylcholine and cholesterol (2:1 mol/mol) in a highly specific manner. The chemical reactivities of the functional groups were determined over the concentration range of 1.0 X 10(-6)-3.0 X 10(-8) M by the method of competitive labelling with 1-fluoro-2,4-dinitrobenzene as the labelling reagent. At concentrations above 3 X 10(-7) M, the amino terminal histidine and the two tyrosine residues showed a marked decrease in reactivity in the presence of liposomes, but the reactivity of the Lys-12 N epsilon-amino group was unaltered. At lower concentrations the Lys-12 reactivity also decreased markedly, owing to a change in the environment of this group. These results indicated that two different forms of glucagon existed over the concentration range studied. Both in the absence and presence of liposomes the Lys-12 N epsilon-amino groups showed a transition in reactivity at 1.8 X 10(-7) M. In the presence of liposomes the other functional groups also showed a transition in reactivity at 2 X 10(-7) M but the change was much smaller. The pattern of reactivities were consistent with the X-ray crystallographic structure of the type 2 glucagon trimer being the predominant species at 10(-6) M, with free monomeric glucagon occurring at 3 X 10(-8) M. A trimerization constant of 4 X 10(13) M-2 at pH 7.5 and 37 degrees C was determined.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0829-8211
pubmed:author
pubmed:issnType
Print
pubmed:volume
68
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
284-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Binding of glucagon to lipid bilayers.
pubmed:affiliation
Department of Chemistry, Faculty of Science, University of Ottawa, Ont., Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't