Construction and characterization of the interdomain chimeras using Cry11Aa and Cry11Ba from Bacillus thuringiensis and identification of a possible novel toxic chimera.
Three structural domains of mosquitocidal Cry11Aa and Cry11Ba from Bacillus thuringiensis were exchanged to produce interdomain chimeras [BAA (11Ba/11Aa/11Aa), ABA (11Aa/11Ba/11Aa), AAB (11Aa/11Aa/11Ba), ABB (11Aa/11Ba/11Ba), BAB (11Ba/11Aa/11Ba), BBA (11Ba/11Ba/11Aa]. Chimeras BAB, BAA, BBA, and AAB formed inclusion bodies in the crystal-negative B. thuringiensis host and produced expected protein bands on SDS-PAGE gel. However, no inclusion body or target protein could be found for chimeras ABA and ABB. In bioassays using the fourth-instar larvae of Culex quinquefasciatus and Aedes aegypti, AAB had ~50 % lethal concentrations of 4.8 and 2.2 μg ml(-1), respectively; however, the rest of chimeras were not toxic. This study thus helps to understand the domain-function relationships of the Cry11Aa and Cry11Ba toxins. The toxic chimera, AAB, might be a candidate for mosquito control as its amino acid sequence is different from the two parental toxins.
College of Life Science, Hunan Normal University, Changsha, People's Republic of China, sunyj@hunnu.edu.cn.
Yunjun
Y
Sun
Qiang
Q
Zhao
Dasheng
D
Zheng
Xuezhi
X
Ding
Jingfang
J
Wang
Quanfang
Q
Hu
Zhiming
Z
Yuan
Hyun-Woo
HW
Park
Liqiu
L
Xia
D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D001427:Bacterial Toxins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D003465:Culex / Q000187:drug effects; D004591:Electrophoresis, Polyacrylamide Gel; D004731:Endotoxins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D004926:Escherichia coli; D006460:Hemolysin Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D007306:Insecticides / Q000737:chemistry* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; C115468:CRY11BB protein, Bacillus thuringiensis; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; D011993:Recombinant Fusion Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis