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Chromosomal replication initiation machinery of low-G+C-content Firmicutes.

ABSTRACT: Much of our knowledge of the initiation of DNA replication comes from studies in the gram-negative model organism Escherichia coli. However, the location and structure of the origin of replication within the E. coli genome and the identification and study of the proteins which constitute the E. coli initiation complex suggest that it might not be as universal as once thought. The archetypal low-G+C-content gram-positive Firmicutes initiate DNA replication via a unique primosomal machinery, quite distinct from that seen in E. coli, and an examination of oriC in the Firmicutes species Bacillus subtilis indicates that it might provide a better model for the ancestral bacterial origin of replication. Therefore, the study of replication initiation in organisms other than E. coli, such as B. subtilis, will greatly advance our knowledge and understanding of these processes as a whole. In this minireview, we highlight the structure-function relationships of the Firmicutes primosomal proteins, discuss the significance of their oriC architecture, and present a model for replication initiation at oriC.

SUBMITTER: Briggs GS

PROVIDER: S-EPMC3457243 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Chromosomal replication initiation machinery of low-G+C-content Firmicutes.

Briggs Geoffrey S GS Smits Wiep Klaas WK Soultanas Panos P

Journal of bacteriology 20120713 19

Much of our knowledge of the initiation of DNA replication comes from studies in the gram-negative model organism Escherichia coli. However, the location and structure of the origin of replication within the E. coli genome and the identification and study of the proteins which constitute the E. coli initiation complex suggest that it might not be as universal as once thought. The archetypal low-G+C-content gram-positive Firmicutes initiate DNA replication via a unique primosomal machinery, quite ...[more]

PMID: 22797751

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Dataset Information

Chromosomal replication initiation machinery of low-G+C-content Firmicutes.

Publications

Chromosomal replication initiation machinery of low-G+C-content Firmicutes.

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