Two essential DNA polymerases at the bacterial replication fork.
DNA replication in bacteria is carried out by a multiprotein complex, which is thought to contain only one essential DNA polymerase, specified by the dnaE gene in Escherichia coli and the polC gene in Bacillus subtilis. Bacillus subtilis genome analysis has revealed another DNA polymerase gene, dnaE(BS), which is homologous to dnaE. We show that, in B. subtilis, dnaE(BS) is essential for cell viability and for the elongation step of DNA replication, as is polC, and we conclude that there are two different essential DNA polymerases at the replication fork of B. subtilis, as was previously observed in eukaryotes. dnaE(BS) appears to be involved in the synthesis of the lagging DNA strand and to be associated with the replication factory, which suggests that two different polymerases carry out synthesis of the two DNA strands in B. subtilis and in many other bacteria that contain both polC and dnaE genes.
Dervyn
E
E
Génétique Microbienne, Institut National de la Recherche Agronomique, Jouy-en-Josas, 78352 Cedex, France.
Suski
C
C
Daniel
R
R
Bruand
C
C
Chapuis
J
J
Errington
J
J
Jannière
L
L
Ehrlich
S D
SD
D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D001426:Bacterial Proteins / Q000096:biosynthesis; D002876:Chromosomes, Bacterial / Q000235:genetics; D004258:DNA Polymerase III / Q000235:genetics / Q000378:metabolism*; D004260:DNA Repair; D004261:DNA Replication / Q000235:genetics; D004269:DNA, Bacterial / Q000096:biosynthesis; D004259:DNA-Directed DNA Polymerase / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D005798:Genes, Bacterial / Q000235:genetics; D020043:Genes, Essential / Q000235:genetics*; D016680:Genome, Bacterial; D020035:Holoenzymes / Q000235:genetics / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D012329:RNA, Bacterial / Q000096:biosynthesis; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D020035:Holoenzymes; D012329:RNA, Bacterial; D011993:Recombinant Fusion Proteins; C074904:DNA polymerase III, alpha subunit; D004258:DNA Polymerase III; D004259:DNA-Directed DNA Polymerase