I am a third year Molecular Biology student at the university of Toronto
and am also taking a microbiology course out of general interest.
I am curious as to the proposed origin of plasmids. I have heard that
bacteria can actually scavenge their surroundings for useful pieces of
DNA.
Most plasmids I have come across thus far have dealt with antibiotic
resistance genes - used for selections. Did these genes evolve only
since the advent of antibiotics this century, or is it believed that they
existed before? ie: were their natural antibiotic agents that existed
before - a sort of interbacterial warfare.
Steve
steven.sanyal at utoronto.ca
