Dear Colleagues:
There is a lot of excellent discussion on this network. Although
most of it is researchers frantically trying to find key information to shed
light on their studies, at other times there is an opportunity to review
fundamental concepts in microbiology.
One topic I'd like your comments on is the role of antibiotics. Certainly
there may be a selective advantage for producers in the competition for
limited space and food, but I am beginning to think this is an indirect
spin-off of their true role:
- Why are most antibiotics produced by organisms with complicated
life-cycles (e.g. vegetative -> spores, larvae -> butterflies)
- It has been speculated that Fleming was far brighter than he let on.
The stories go that the windows in his lab were sealed with paint and not
open to outside contaminants, the strain of penicillium used was a low
producer (sub-sequent selection has yielded high producers), and he had a
lot of other bright ideas such as lysozyme.
My view, therefore, is that the role of antibiotics is primarily to shut
down or inhibit biochemical pathways in the producer so that it can mature
into a different form. It just so happens that this inhibition works on
other life-forms. If so, even in relatively simple life-forms, antibiotics are
being produced to regulate or change pathways.
We are just identifying "the tip of the iceberg" with regards to new
pharmaceuticals or therapeutic agents.
Comments....John Cherwonogrodzky
