Linked Life Data

18957605

Source:http://linkedlifedata.com/resource/pubmed/id/18957605

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 11
pubmed:dateCreated
2008-10-29
pubmed:abstractText
Cyt1Aa is a delta-endotoxin protein that is produced by Bacillus thuringiensis subsp. israelensis. It is a membrane pore-forming toxin that is lethal to insect larvae and is broadly cytolytic to vertebrate as well as invertebrate cells. Cyt1Aa is produced as a protoxin of 27 kDa. Proteolytic activation results in a reduction of the molecular mass to approximately 23-24 kDa and a threefold increase in activity. In this research, Cyt1Aa crystals were purified from B. thuringiensis IPS78/11 harbouring the expression vector pHT-cyAp20. The activity of the activated form of Cyt1Aa (23-24 kDa) was examined on a pathogenic strain of the Gram-negative Escherichia coli and the Gram-positive species Staphylococcus aureus. The Cyt1Aa minimal inhibitory concentration for E. coli and S. aureus was 1.25 and 5 microg ml(-1), respectively. Cyt1Aa was found to be bactericidal for E. coli, whereas it was bacteriostatic for S. aureus. Furthermore, Cyt1Aa increased the lethal effect when acting in combination with antibiotics. The association of Cyt1Aa with cells of these two bacteria was demonstrated by Western blot analysis using antibodies against the whole delta-endotoxin crystal. Scanning electron microscopy displayed damage to Cyt1Aa-treated cells. Ion imbalance due to damage of the cell walls and membranes was confirmed by X-ray microanalysis. These experiments show that Cyt1Aa has an antibacterial effect on pathogenic species and demonstrate, apparently for the first time, that exogenous Cyt1Aa has a bactericidal effect upon Gram-negative bacteria.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1350-0872
pubmed:author
pubmed:issnType
Print
pubmed:volume
154
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3529-36
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Antibacterial activity of Cyt1Aa from Bacillus thuringiensis subsp. israelensis.
pubmed:affiliation
Department of Chemical Engineering and Biotechnology, Ariel University Center of Samaria, Ariel, Israel. rivkac@yosh.ac.il
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't