So far, there are 5 distinct DNA polymerases have been found in E. coli cell: Pol I, Pol II, Pol III, Pol IV, and Pol V. While Pol III (Pol III Holoenzyme) is a primary polymerase involved in DNA replication, the others take part in other processes such as DNA repair, translesion synthesis … rather than in chromosome replication. Pol I is encoded by polA gene and belongs to the A family. During DNA replication, PoI synthesizes the gap between Okazaki fragments to complete lagging product synthesis by its 5′-3′ polymerase activity. Continue Reading →