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.
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