Linked Life Data

8505321

Source:http://linkedlifedata.com/resource/pubmed/id/8505321

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
1993-7-7
pubmed:abstractText
Staphylococcal alpha-toxin is a single-chain polypeptide with a molecular weight of 34,000 that hexamerizes in lipid bilayers to form pores of 1-1.5 nm effective diameter in membranes. We demonstrate that limited proteolysis of purified alpha-toxin with proteinase K generates a hemolytically active product that yields one major protein band of 17-18 kDa in SDS-polyacrylamide gel electrophoresis. The 17-18-kDa protein band harbors two major fragments of similar size representing the N- and C-terminal halves, which remain associated with each other in non-denaturing buffers but dissociate in 6 M urea. Dissociation in urea leads to loss of hemolytic activity. In contrast, unnicked alpha-toxin is not inactivated by urea. Nicked, hemolytically active alpha-toxin forms hexamers on erythrocyte membranes and on lymphocytes and monocytes. However, the nicked toxin can only lyse erythrocytes and fails to permeabilize nucleated cells. Osmotic protection experiments indicate that the size of pores generated by the nicked toxin is considerably smaller (0.6-0.9 nm effective diameter) than that generated by native toxin. The collective results do not support a previous proposal that different functions of alpha-toxin are contained in separate domains of the molecule.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
268
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11963-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Altered pore-forming properties of proteolytically nicked staphylococcal alpha-toxin.
pubmed:affiliation
Institute of Medical Microbiology, University of Mainz, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't