Two novel dissimilar crystal proteins, Cry5Ca1 and Cry5Da1, synergistically act against Meloidogyne incognita and delay Cry5Ba-based nematode resistance.

Two novel dissimilar crystal proteins, Cry5Ca1 and Cry5Da1, synergistically act against Meloidogyne incognita and delay Cry5Ba-based nematode resistance. Appl Environ Microbiol. 2017 Jul 14;: Authors: Geng C, Liu Y, Li M, Tang Z, Muhammad S, Zheng J, Wan D, Peng D, Ruan L, Sun M Abstract Cry proteins of Bacillus thuringiensis have been successfully used as biopesticides and transgenic crops throughout the world. However, resources against the most serious agricultural pathogens, plant root-knot nematodes, are limited. The genomes of several highly nematicidal virulent Bt strains from our laboratory have been sequenced, facilitating the identification of novel Cry proteins and other virulence factors. We identified two novel Cry proteins, Cry5Ca1 and Cry5Da1, that exhibit high toxicity against Meloidogyne incognita Using the Caenorhabditis elegans model, both Cry5 toxins showed to negatively affect nematode lifespan, fertility and survival. The LC50 values of Cry5Ca1 and Cry5Da1 were 57.22 μg/ml and 36.69 μg/ml, respectively. Moreover, the synergistic effect (synergism factor, 1.61 to 2.04) were observed on nematicidal toxicity between Cry5Ca1 and Cry5Da1, which is accordant with the phylogenetic results that domain II of the two novel Cry5 toxins evolving into two independent clades. Through comparison of the toxicity depressed degree in the β-methylgalactoside detoxification test, we found that the novel toxin Cry5D possess diffe...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research