Mammalian DNA polymerase beta can substitute for DNA polymerase I during DNA replication in Escherichia coli.

摘要: Mammalian DNA polymerase beta is the smallest known eukaryotic and expressed as an active protein in Escherichia coli harboring a plasmid containing its cDNA. Since some catalytic functions of E. I are similar, we wished to determine if could substitute for bacteria. We found that expression mammalian restored growth I-defective bacterial mutant. Sucrose density gradient analysis revealed complements replication defect mutant by increasing rate joining Okazaki fragments. These findings demonstrate beta, believed function repair cells, can also replication. Moreover, this complementation system will permit study vivo altered species currently precluded difficulty isolating mutants cells.