Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1988-3-23
pubmed:abstractText
The Tsx protein from the outer membrane of Escherichia coli is known to be involved in the permeation of nucleosides across the outer membrane under limiting substrate conditions. We purified Tsx from an E. coli strain that overproduces Tsx. The purified protein was still functional since it could neutralize the Tsx-specific bacteriophage T6 in vitro. When the purified Tsx was reconstituted into a lipid bilayer, there was a large increase of the membrane conductance, indicating pore-forming activity of Tsx in vitro. This increase could be strongly blocked with adenosine and to a much lesser extent with cytidine. Titration of the pore conductance with adenosine or cytidine suggested the presence of a binding site for nucleosides in the Tsx pore, with a Ks of 6 X 10(-4) and 2 X 10(-2) M for adenosine and cytidine, respectively. We propose that the Tsx protein functions in vivo as a pore that specifically facilitates the permeation of nucleosides across the outer membrane due to its binding site for nucleosides.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
263
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2493-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Pore-forming activity of the Tsx protein from the outer membrane of Escherichia coli. Demonstration of a nucleoside-specific binding site.
pubmed:affiliation
Fakultät für Biologie, Universität Konstanz, Federal Republic of Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't