The splicing of group I and group II introns involves two sequential transesterification reactions. What does this mechanism ensure?
Explanation
The splicing of group I and group II introns proceeds via two successive transesterification reactions. In each step, one phosphodiester bond is broken and another is formed. This mechanism is energetically efficient because it does not require an external energy source like ATP, as the number of phosphodiester bonds is conserved throughout the process.
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