Project description:CCA-adding enzymes are highly specific RNA polymerases that synthesize and maintain the sequence CCA at the tRNA 3‘-end. Here, we investigated the impact of cold adaptation on the reactivity and specificity of CCA-adding enzymes from psychrophilic bacteria. A comparative study of the corresponding enzymes from closely related psychro-, meso-, and thermophilic Bacillales indicates that the cold-adapted enzymes show a considerable error rate during CCA synthesis, resulting in additional incorporations of C and A residues. It seems that the activity of psychrophilic CCA-adding enzymes is not only achieved at the expense of structural stability, reaction velocity and substrate affinity, but also results in a reduced polymerization fidelity.
