You Insert a Gene for Tetracycline Resistance into One Plasmid

question 31

Multiple Choice

You insert a gene for tetracycline resistance into one plasmid and a gene for ampicillin resistance into another plasmid.You successfully introduce both plasmids into a sample of E.coli cells,but fail to grow any of them in culture medium with both antibiotics present in it.What could best explain the problem?

• A)Random mutation has inactivated the antibiotic resistance genes
• B)Plasmid incompatibility will not allow both plasmids to persist
• C)E)coli cannot maintain two plasmids
• D)The plasmid(s)have integrated into the bacterial chromosome
• E)A phage has neutralized one of the plasmids