Identification of a novel enhancin-like gene from Bacillus thuringiensis

Abstract

An enhancin-like gene was cloned from Bacillus thuringiensis (Bt) strain GS8 isolated from soil samples in china. The sequence analysis revealed that an open reading frame (ORF) of 2202 nucleotides encoding a protein containing 733 amino acids with a molecular mass of 84 kDa. The enhancin-like protein showed 100% identity to Bel protein (FJ644935) and 23%–41% identity to viral enhancin proteins; in the 252 to 261 amino-acid sequence of enhancin-like protein, a conserved metal binding motif (HEIAH) similar to that in the reported bacterial enhancin-like proteins was found (HEXXH in viral enhancin protein), which indicated that the enhancin-like protein belongs to metalloprotease. The purified enhancin-like protein was fed together with Cry9Ea to Spodopera exigua and Trichoplusia ni larvae, but no significant increase in toxicity was observed.

Key words： Bacillus thuringiensis; enhancin-like gene; Cry9Ea protein; synergism

Acknowledgements

This work was supported in part by the National Basic Research Program of China (No. 2009CB118902), the National Science Foundation of China (No. 30771447), and the Earmarkal Fund for Modern Agriculture Technology Research System.

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