An analysis of the genes encoding the 51.4- and 41.9-kDa toxins of Bacillus sphaericus 2297 by deletion mutagenesis: the construction of fusion proteins.
A series of deletion mutants have been constructed, in which varying numbers of amino acids have been deleted from both the N- and C-termini of both the 51.4- and 41.9-kDa toxins of Bacillus sphaericus. The results show that between 34-39 and 52-54 amino acids respectively at the N- and C-termini of the 51.4-kDa protein, are not essential for toxicity. In the case of the 41.9-kDa protein, the removal of only 7 amino acids from the C-terminus abolishes toxicity whilst at least 17 amino acids can be deleted from the N-terminus without loss of toxicity. A fusion protein with the 51.4-kDa derived sequence N-terminal to the 41.9-kDa sequence yielded a protein of Mr 87 kDa which was not toxic by itself. When supplemented with cells expressing only the 51.4-kDa protein, toxicity was restored. In contrast, another fusion protein, in which the gene order was reversed, was shown to be fully active in toxicity assays.
Oei
C
C
Institute of Molecular and Cell Biology, National University of Singapore.
Hindley
J
J
Berry
C
C
D000595:Amino Acid Sequence; D000818:Animals; D001407:Bacillus / Q000235:genetics*; D001427:Bacterial Toxins / Q000235:genetics*; D001483:Base Sequence; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D003465:Culex / Q000235:genetics / Q000382:microbiology; D004269:DNA, Bacterial / Q000737:chemistry; D015870:Gene Expression; D005798:Genes, Bacterial; D007814:Larva / Q000235:genetics / Q000382:microbiology; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011993:Recombinant Fusion Proteins / Q000235:genetics
D001427:Bacterial Toxins; D004269:DNA, Bacterial; D011993:Recombinant Fusion Proteins