Comparison of CD composition produced by chimeric CGTases.

Using 12 chimeric cyclomaltodextrin glucanotransferases (CGTases) constructed from two genes, the CGTase gene from the alkalophilic Bacillus sp. strain No. 38-2 (CGTase 38-2 gene) and the CGTase gene from the alkalophilic Bacillus sp. strain No. 17-1 (CGTase 17-1 gene), we compared the effect of those chimeric enzymes on cyclodextrin (CD) production, especially on the composition of the CDs produced. It was found that the N-terminal and the C-terminal segments were important for CD production. Chimeric enzymes that contained the N-terminal and the C-terminal segments derived from CGTase 38-2 produced large amounts of CD, and especially a higher proportion of alpha-CD than those of other chimeric enzymes.