sentence: Methylglyoxal and acetate were finally transformed into acetylacetone by Dke1.To test the hypothetical acetylacetone biosynthetic pathway , acetylacetone-cleaving enzyme ( Dke1 ) from A. johnsonii ( accession No. Q8GNT2.1 ) was cloned into plasmid pETDuet-1 , and then the recombinant plasmid was introduced into E. coli BL21 ( DE3 ) to construct an acetylacetone producing strain .