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ANNETTE DEICHMANN AND KLAUS DEICHMANN
mcr
e
~
transformation
""
0
restriction
digest
genomic DNA
ligation
/
0
recombinant plasmid
~
0
CaCI + heat/cold
electric. impulse
,
0 0
c@
0
plasmids
bacterial DNA
host cell
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Fig. 1. Fragments of genomic DNA are cloned into a plasmid to form a recombinant plasmid.
These are transformed into E. coli host cells (mcr = multiple cloning region).
• An origin of replication which initiates their replication and keeps the
number of copies within a cell at a characteristic level.
• An optional multiple cloning region (MCR), which is a short sequence
bearing unique recognition sites for many restriction enzymes. The MCR
allows site-directed cloning of an insert.
• Antibiotic resistance genes providing a selective advantage to transformed bacterial host cells.