Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2008-9-2
pubmed:abstractText
Development of targeted biological agents against agricultural insect pests is of prime importance for the elaboration and implementation of integrated pest management strategies that are environment-friendly, respectful of bio-diversity and safer to human health through reduced use of chemical pesticides. A major goal to understand how Bt toxins work is to elucidate the functions of their three domains. Domains II and III are involved in binding specificity and structural integrity, but the function of Domain I remains poorly understood. Using a Manduca sexta BBMV (brush border membrane vesicles) system, we analyzed its responses to Cry1Aa 15 single-point mutations with altered Domain I helix 4 residues. Light scattering assay showed that toxicity was almost lost in 3 mutants, and we observed significantly reduced toxicity in other 7 mutants. However, 5 mutants retained wild-type toxicity. Using computer software, we simulated the three-dimensional structures of helix 4. Both experimental and bioinformatic analysis showed that residues in Cry1Aa Domain I helix 4 were involved in the formation of ion channels that is critical for its insect toxicity.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Dec
pubmed:issn
1006-9305
pubmed:author
pubmed:issnType
Print
pubmed:volume
45
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
561-8
pubmed:year
2002
pubmed:articleTitle
The toxicity test and hypothetical model of Bacillus thuringiensis Cry1Aa helix4.
pubmed:affiliation
Peking University, Beijing, China.
pubmed:publicationType
Journal Article