AAT Bioquest

Does DNA being circular or linear directly affect the speed of DNA replication?

Posted May 16, 2022


Prokaryotes have circular DNA and a faster speed of DNA replication, whereas eukaryotes have linear DNA and a slower speed of DNA replication. While the shape of the DNA is thought to play a role in the speed of DNA replication, it does not directly affect the DNA replication speed. Instead, it is the size of the DNA that directly affects the speed of DNA. 

Eukaryotic DNA is larger and linear, and has multiple replication origins to compensate for its larger size. The additional replication origins slows down the speed of DNA replication in eukaryotes. On the other hand, prokaryotic has only one point of replication. This indicates that while shape may be a factor, it’s the size that directly affects the speed of DNA replication.  Eukaryotes also have a distinct process for replicating the telomeres at the ends of their chromosomes. Prokaryotes have no ends to synthesize. 

Additional resources

Effect of the matrix on DNA electrophoretic mobility

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