Patent ID: 6090931
Filing Date: 2000-07-18
Classification: A01N,C07K,C12N,C12R

Abstract:
A process for identifying a recombinant DNA sequence encoding a modified B.t. crystal protein toxin which has an altered host range or increased toxicity against at least one target lepidopteran insect host comprising the steps of:(a) replacing at least a part of a variable region of a first parent DNA sequence encoding a lepidopteran active B.t. crystal protein toxin with at least a part of a variable region of at least one other patent DNA sequence encoding a different lepidopteran active B.t. crystal protein toxin to obtain a recombinant DNA sequence encoding a modified B.t. crystal protein toxin which is different from any of said crystal protein toxins encoded by said parent DNA sequences;(b) producing said modified B.t. crystal protein toxin from said recombinant DNA sequence; and(c) assaying said modified B.t. crystal protein toxin to verify whether said modified B.t. crystal protein toxin has an altered host range or increased toxicity against at least one target lepidopteran insect host as compared to any of said crystal protein toxins encoded by said parent DNA sequences; whereby, if verified, said recombinant DNA sequence is identified as one encoding a modified B.t. crystal protein toxin having an altered host range or increased toxicity.