Sequence analysis of a new chitinase gene from a native Bacillus thuringiensis strain

SAUKA, D.H.; BERRETTA, M.F.; ONCO, M.I.; BENINTENDE, G.B.

Mar del Plata

Congreso; VIII Congreso de Microbiología General; 2012

SAMIGE

The entomopathogenic bacterium Bacillus thuringiensis has been used as a pesticidal agent for years. It is known that endogenous chitinase plays an advantageous position in the pathogenicity of this bacterium to insects. The chitinase gene sequence was obtained as an accessory result from a study aimed at the search for insecticidal genes in native strains using the Genome Sequencer FLX system (454) (INDEAR, Rosario). The sequence was 2025 nucleotides long, encoding 674 amino acid residues with a predicted molecular weight of 74.2 kDa and a pI value of 5.97. BLAST search showed a high degree of similarity with other Bacillus chitinases. In addition, the deduced amino acid sequence showed that the protein contained an amino terminus signal peptide and consisted of a single catalytic domain, a fibronectin type III domain and a chitin-binding domain. All three domains showed conserved sequences when compared to other bacterial chitinase sequences. To the best of our knowledge, this is the first report of a chitinase gene in a native to Argentina B. thuringiensis strain.