Variant Cry3 Toxin Mutations for Resistant Coleopteran Control
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Solution Overview
Problem
There is a continuous need for new forms of pesticidal toxins to effectively control insect pests that devastate agricultural crops, as existing methods may not provide sufficient yield protection and pest resistance.
Innovation Solution
Development of recombinant nucleic acid molecules and polypeptides encoding variant Cry3 amino acid sequences with specific mutations, such as a glutamic acid residue at position 316, a leucine residue at position 482, and a lysine residue at position 483, which are used to transform bacteria and plants to confer enhanced pesticidal activity against coleopteran pests.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing pesticidal toxins are used to control insect pests, then yield protection is provided, but pest resistance develops and insufficient yield protection occurs
Solution Approach 1:
The patent applies parameter changes by modifying the amino acid sequence of the Cry3 toxin protein through site-directed mutagenesis. Specific amino acid residues are changed to alter the toxin's properties, creating variant toxins with improved pesticidal activity against resistant pest populations while maintaining their fundamental mechanism of action
Solution Approach 2:
The patent creates composite pesticidal compositions by combining variant Cry3 toxin proteins with other pesticidal agents or formulations. This composite approach enhances overall pest control effectiveness and delays resistance development by targeting pests through multiple mechanisms simultaneously
2Reliability
If new pesticidal toxin forms are developed, then pest resistance is overcome, but complexity of toxin development increases
Solution Approach 1:
The patent employs preliminary action by using site-directed mutagenesis to pre-engineer specific amino acid changes in the toxin sequence before deployment. This allows researchers to predict and create resistance-breaking variants in the laboratory before field application, rather than waiting for resistance to develop naturally
Solution Approach 2:
The patent uses copying by creating recombinant DNA copies of the modified toxin genes and expressing them in transgenic plants or microbial systems. This allows the engineered toxin sequence to be replicated and deployed at scale through genetic material rather than requiring complex chemical synthesis of each toxin molecule
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The variant Cry3 sequences demonstrate improved pesticidal activity, increasing mortality and reducing feeding or growth of target pests by at least 5% to 100% compared to wild-type sequences, making them suitable for agricultural use in transgenic plants and microbial formulations.
Implementation Method 1
This toxin binds to apical brush border receptors in the midgut of the target larvae and inserts into the apical membrane creating ion channels or pores, resulting in larval death
Implementation Method 2
The ingested protoxin is hydrolyzed by proteases in the insect digestive tract to an active toxic molecule
Data Source
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AI summary
Compositions and methods for conferring pesticidal activity to bacteria, plants, plant cells, tissues and seeds are provided. Compositions comprising a coding sequence for pesticidal polypeptides are provided. The coding sequences can be used in DNA constructs or expression cassettes for transformation and expression in plants and bacteria. Compositions also comprise transformed bacteria, plants, plant cells, tissues, and seeds. In particular, nucleic acid molecules encoding variant Cry3 sequences are provided. Additionally, amino acid sequences corresponding to the polynucleotides are encompassed.