title: Carboxy-terminal extension effects on crystal formation and insecticidal properties of Cry15Aa.
abstract: Cry15Aa protein, produced by Bacillus thuringiensis serovar thompsoni HD542, in a crystal together with a 40 kDa accompanying protein, is one of a small group of non-typical, less well-studied members of the Cry family of insecticidal proteins, and may provide an alternative for the more commonly used Cry proteins in insect pest management. In this study we examined the role of the C-terminal part of Cry15Aa and of the 40 kDa protein in crystal formation in recombinant B. thuringiensis. The contribution of the 40 kDa protein and of the Cry15Aa carboxy-terminal sequence for crystal formation, crystal solubilization, and insecticidal properties was assessed. No significant differences in toxicity against Cydia pomonella, before or after in vitro solubilization of crystal-spore preparations, were found. Although the 40 kDa protein significantly contributes to in vitro solubility and in vivo crystal formation of Cry15Aa, no direct evidence for involvement of the 40 kDa protein in toxicity of Cry15Aa was found.
authors: University of Plovdiv Paisii Hilendarski, 4000 Plovdiv, Bulgaria. naimov0@uni-plovdiv.bg
authors: Samir
authors: S
authors: Naimov
authors: Rumyana
authors: R
authors: Valkova
authors: Stefan
authors: S
authors: Dukiandjiev
authors: Ivan
authors: I
authors: Minkov
authors: Ruud A
authors: RA
authors: de Maagd
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry* / Q000502:physiology / Q000648:ultrastructure; D003460:Crystallization; D018360:Crystallography, X-Ray; D004731:Endotoxins / Q000737:chemistry* / Q000502:physiology; D006460:Hemolysin Proteins / Q000737:chemistry* / Q000502:physiology / Q000648:ultrastructure; D007306:Insecticides / Q000737:chemistry*; D009036:Moths; D010572:Pest Control, Biological; D012995:Solubility
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis