Dy3+ and Nd3+ induced genetic mutation of bacillus α-amylase

After treatment with DyCl3 and NdCl3, two strains of mutated bacilli showing increased α-amylase activity were isolated. The α-amylase genes were amplified, cloned, and sequenced. Sequencing revealed that there were either 11 or 14 bases altered in the two genes. These alterations took the form of base substitutions, and transversion was more common than transition. Based on these results, it was concluded that the rare earth compounds DyCl3 and NdCl3 were mutagens.