The present invention relates generally to modified Bt insecticidal
crystal proteins, also referred to as mutant toxins, with enhanced
toxicity against a variety of insect genera, particularly mosquitos. The
invention provides modified Bt Cry4Ba and Cry19Aa proteins, or mutant
toxins, which have toxicity-enhancing sequence modifications at one or
more positions within the amino acid sequence of the protein. The
invention also provides polynucleotides encoding modified Cry4Ba and
Cry19Aa proteins. The invention also provides insecticidal compositions
comprising mutant toxins with a new or broadened insecticidal spectrum,
and insecticidal compositions comprising polynucleotides encoding the
modified Cry4Ba and Cry19Aa proteins.
