Practice question

Bacterial RNA polymerase elongates roughly 40-50 nucleotides per second, significantly slower than DNA polymerase III synthesizing DNA near 750-1000 nucleotides per second during replication. Reduced rate attributed to lower processivity because transcription includes frequent pausing, backtracking for proofreading via GreA/GreB, waiting for regulatory factors like NusA, and requirement to unwind DNA continuously. Replication utilizes sliding clamp beta conferring high processivity and topoisomerases cooperating efficiently. Transcriptional pausing facilitates coupling with translation, co-transcriptional folding, attenuation, and regulatory checkpoints absent in highly processive replication optimized for rapid genome duplication.