Many of the antibiotics we use today are derived from molecules discovered during large scale screens of microorganisms done between 1940-1960. Organisms such as Penicillium and Streptomyces evolved these compounds to use against competitor microorganisms int their ecosystems. In the case of penicillin and streptomycin, we also found them useful against the bacteria which compete with us for the resources in our bodies - bacterial like staphylococcus aureus or tuberculosis.
Over the decades since penicillin came into use, staph aureus has evolved defenses against it. Chemists and drug companies modified penicillin to overcome these defenses, and staph went on to evolve defenses against these modifications. It has become an arms race pitting the laboratory against the evolution of staph aureus.
But consider - what about the organisms that made these drugs in the first place? Wouldn't the enemies of Penicillium have evolved defenses against penicillin at the same rate that staph aureus evolved defenses against penicillin as used by humans? It is bacteria fighting both us and Penicillium - in both cases likely able to evolve at similar rates. The antibiotic arms race is likely going on in the soil as well - and at the same pace as in the hospital!
I propose that laboratories should go back to the soil and repeat their large scale microorganism screenings every 20 years or so. It may be that in the interim, evolution will have produced new compounds in answer to evolutionary resistance of their enemies.
Another possibility would be to screen ancient or fossil deposits for useful antibiotics. It may be that 10 million years ago, soil microbes made compounds that were effective then, but became ineffective over time and were phased out by the organisms making them - These compounds might be effective again for our uses. Even if the organisms which made them are dead, it might be possible to detect these compounds in coal and other ancient biologic material - or in "fossil" water from underground lakes or other sources where evolution may have taken place in isolation from the ecologic arms races on the surface.-- bungston, Apr 10 2004 Retroposons http://en.wikipedia.org/wiki/Retroposon"Selfish DNA" [dpsyplc, Oct 04 2004, last modified Oct 21 2004] Restriction Enzymes http://nist.rcsb.or...lecules/pdb8_1.htmlHow bacteria fight back. [dpsyplc, Oct 04 2004, last modified Oct 21 2004] Bacteriophage Viruses from Russia http://www.nature.c...20422/020422-4.htmlFor antibiotic resistant diseases [philmckraken, Oct 04 2004, last modified Oct 21 2004] How about copper coated antibiotics?-- bristolz, Apr 10 2004 I drank a lot of the water you're spreaking of as a kid, and have had enough innoculum by now to know the difference -- none, that I know of.
Nothing wrong with your approach, [bungston]. What you propose is done with bioassays of immunoglobulins for vaccines -- you're extending that to drug discovery, a field with many more variables. I'll provide a link to deepen your understanding of how microorganisms evolve.-- dpsyplc, Apr 11 2004 The Russians/Soviets have for many years been experimenting with using bacteriophage viruses as antibiotics (see link)-- philmckraken, Jul 07 2004 //Wouldn't the enemies of Penicillium have evolved defenses against penicillin at the same rate that staph aureus evolved defenses against penicillin as used by humans? It is bacteria fighting both us and Penicillium - in both cases likely able to evolve at similar rates.//
Not necessarily. Penicillin resistance (as with pretty much all antibiotic resistances) pre-existed human use. But only in niches where the bacteria would be exposed. While the initial rate of evolution of high resistance may be low, once it exists it can be spread around essentially between 'all' bacteria relatively quickly.
//I propose that laboratories should go back to the soil and repeat their large scale microorganism screenings every 20 years or so.//
Actually there are scientists constantly searching for new antibiotics already. If you want to pump some money in so more can be done then go ahead. Partly the problem is that the same (or similar) antibiotics keep being re-discovered, which suggests that most of the diversity has already been found. - So people are trying to look in different places.
//Another possibility would be to screen ancient or fossil deposits for useful antibiotics. It may be that 10 million years ago, soil microbes made compounds that were effective then, but became ineffective over time and were phased out by the organisms making them//
This, on the other hand, could be a novel idea. Not easy to do, though. You need to do more than just detect a strange compound. An alternate tactic would be to try to reconstruct long enough DNA sequences. This might work practically, since often the genes for resistance are adjacent to the genes for production. After introducing such DNA into a safe strain of bacteria one would screen for the ability to kill off another strain. But this is still a long shot, I fear.-- Loris, Jul 07 2004 penicillin as you may know is a type of mold. As Loris has said, there are new antibiotics being discovered as I type this. There are many types of fungus in the Amazon rain forest, and a lot of reasearch is being conducted on fungus in the Amazon. There are other problem with injecting your body with fungus other than Baceria mutating and becomming immune to the fungus. If a person has an infection that has caused a lowered immune system they can get a secondary fungal infection that can be as deadly as the origional bacteria. Also Antibiotics do nothing against the viral infections that plague us today.. In my oppinion more research needs to be done in anti-virual than in anti-bacterial.. -DL-- dlapham, Jul 07 2004 random, halfbakery