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Name: Marta
Status: Student
Grade:  Other
Location: Outside U.S.
Country: Spain
Date: Summer 2009


Question:
E. coli DNA is circular and single copy. Does it mean that there is just one kind of strands? Does it means that there is no complementary strands? If this is the case, how does replication works? If not, what does it mean single copy? If there are complementary copies of the same plasmid sequence, they can easily paire and become a double stranded circular DNA isn' t it? And finally, if you can have 2 complementary strands, are both strands transcribed? Thank you very much!



Replies:
Single copy means that there is one copy of double stranded DNA, not a single copy of DNA strands.

Ron Baker, Ph.D.


All DNA is double stranded but e Coli only has one circular chromosome. It can replicate just the same way as eukaryotic chromosomes do.

Vanhoeck



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