title: Cloning, sequencing, and expression of a gene encoding a 100-kilodalton mosquitocidal toxin from Bacillus sphaericus SSII-1.
abstract: A cosmid library was prepared from a partial BamHI digest of total DNA from Bacillus sphaericus SSII-1. Two hundred fifty Escherichia coli clones were screened for toxicity against larvae of the mosquito Culex quinquefasciatus. One toxic clone, designated pKF2, was chosen for further study. Two toxic subclones, designated pXP33 and pXP34, obtained by ligating PstI-derived fragments of pKF2 into pUC18, contained the same 3.8-kb fragment, but in opposite orientations. Sequence analysis revealed the presence of an open reading frame corresponding to a 100-kDa protein and the 3' end of a further open reading frame having significant homology to open reading frames of transposons Tn501 and Tn21. The sequence of the SSII-1 toxin was compared with those of known toxins and was found to show regional homology to those of ADP-ribosyltransferase toxins. The distribution of the toxin gene among other B. sphaericus strains was examined.
authors.affiliation: Institute of Molecular and Cell Biology, National University of Singapore, Republic of Singapore.
authors.forename: T
authors.initials: T
authors.lastname: Thanabalu
authors.forename: J
authors.initials: J
authors.lastname: Hindley
authors.forename: J
authors.initials: J
authors.lastname: Jackson-Yap
authors.forename: C
authors.initials: C
authors.lastname: Berry
mesh_terms: D000595:Amino Acid Sequence; D001407:Bacillus / Q000235:genetics*; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics*; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D003360:Cosmids; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D014170:Transformation, Genetic
chemical_list: D001427:Bacterial Toxins; C068603:mosquitocidal toxin SSII-1