Participation of valine 171 in alpha-Helix 5 of Bacillus thuringiensis Cry1Ab delta-endotoxin in translocation of toxin into Lymantria dispar midgut membranes.
The Cry1Ab δ-endotoxin V171C mutant protein exhibits a 25-fold increase in toxicity against Lymantria dispar, which correlates with a faster rate of partitioning into the midgut membrane and slightly decreased protein stability. This is an insect-specific mechanism; similar results were not observed in Manduca sexta, another Cry1Ab δ-endotoxin-susceptible insect.
Alzate
Oscar
O
Biochemistry Department, The Ohio State University, 484 W. 12th Avenue, Columbus, Ohio 43210, USA.
Osorio
Cristina
C
Florez
Alvaro M
AM
Dean
Donald H
DH
D000818:Animals; D001413:Bacillus thuringiensis / Q000472:pathogenicity*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D004731:Endotoxins / Q000235:genetics* / Q000378:metabolism*; D006460:Hemolysin Proteins / Q000235:genetics* / Q000378:metabolism*; D007915:Lepidoptera / Q000382:microbiology*; D007928:Lethal Dose 50; D018402:Manduca / Q000382:microbiology; D008958:Models, Molecular; D020125:Mutation, Missense; D021381:Protein Transport; D016019:Survival Analysis; D014633:Valine / Q000235:genetics* / Q000378:metabolism*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D014633:Valine