Fig. 5: Bidirectional Circular DNA Replication in Bacteria

DNA replication (arrows) occurs in both directions from the origin of replication in the circular DNA found in most bacteria. All the proteins involved in DNA replication aggregate at the replication forks to form a replication complex called a replisome. The lagging DNA strand loops out from the leading strand and this enables the replisome to move along both strands pulling the DNA through as replication occurs. It is the actual DNA, not the DNA polymerase that moves during bacterial DNA replication.

Illustration of Bidirectional Circular DNA Replication in Bacteria.jpg by Gary E. Kaiser, Ph.D.
Professor of Microbiology, The Community College of Baltimore County, Catonsville Campus
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Last updated: August, 2018
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