Characterization of Two Novel Bacillus thuringiensis Cry8 Toxins Reveal Differential Specificity of Protoxins or Activated Toxins against Chrysomeloidea Coleopteran Superfamily
| Autor: | Geng Yongxin, Huang Shizhi, Jie Zhang, Changlong Shu, Alejandra Bravo, Guixin Yan, Mario Soberón, Geng Lili |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
Chrysomeloidea Health Toxicology and Mutagenesis lcsh:Medicine dual mode of action Toxicology medicine.disease_cause 01 natural sciences Microbiology insecticidal activity 03 medical and health sciences Bacillus thuringiensis medicine Bioassay Coleopteran 030304 developmental biology 0303 health sciences Larva Chymotrypsin biology Cry protoxin Toxin lcsh:R fungi biology.organism_classification Crucifer 010602 entomology cry8 genes Anoplophora biology.protein |
| Zdroj: | Toxins Volume 12 Issue 10 Toxins, Vol 12, Iss 642, p 642 (2020) |
| ISSN: | 2072-6651 |
| DOI: | 10.3390/toxins12100642 |
| Popis: | Scarabaeoidea and Chrysomeloidea insects are agriculture-destructive coleopteran pests. Few effective Bacillus thuringiensis (Bt) insecticidal proteins against these species have been described. Bt isolate BtSU4 was found to be active against coleopteran insects. Genome sequencing revealed two new cry8 genes in BtSU4, designated as cry8Ha1 and cry8Ia1. Both genes expressed a 135 kDa protoxin forming irregular shape crystals. Bioassays performed with Cry8Ha1 protoxin showed that it was toxic to both larvae and adult stages of Holotrichia parallela, also to Holotrichia oblita adults and to Anoplophora glabripennis larvae, but was not toxic to larval stages of H. oblita or Colaphellus bowringi. The Cry8Ia1 protoxin only showed toxicity against H. parallela larvae. After activation with chymotrypsin, the Cry8Ha1 activated toxin lost its insecticidal activity against H. oblita adults and reduced its activity on H. parallela adults, but gained toxicity against C. bowringi larvae, a Chrysomeloidea insect pest that feeds on crucifer crops. The chymotrypsin activated Cry8Ia1 toxin did not show toxicity to any one of these insects. These data show that Cry8Ha1 and Cry8Ia1 protoxin and activated toxin proteins have differential toxicity to diverse coleopteran species, and that protoxin is a more robust protein for the control of coleopteran insects. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
| Nepřihlášeným uživatelům se plný text nezobrazuje | K zobrazení výsledku je třeba se přihlásit. |