Identification of a novel enhancin-like gene from Bacillus thuringiensis

摘要

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.