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Ok, let's go over this again.
E. coli out-competes other organisms only in reduced oxygen conditions. If E. coli actually could out-compete aerobic organisms, then it would NOT be useful as an indicator of human pathogens. Human pathogens require the conditions in human digestive systems in order to grow - lack of oxygen is important. Can you grow Salmonella aerobically? Sure, in the lab. But for Salmonella to survive and grow in food, to give food poisoning problems, the temperature of the food has to be warm enough, but not too warm, which means oxygen in the food is limited AND competing organisms are limited.
PLEASE, understand that microbiologists are missing the point when they say that E. coli can grow aerobically. It does happen, but ONLY IF competing aerobic organisms are not present. Very particular growth conditions are required. You must select against the growth of other aerobic organisms. So, in the lab, the right temperature, rich medium, often antibiotics, and NO SIGNIFICANT NUMBERS OF COMPETING BACTERIA are all required to grow E. coli in fully aerobic conditions.
That's what most laboratory, not-familiar-with-the-real-world, work-with-only-one-species-at-a-time microbiologists don't understand. Competition is important in the real world.
If you want, you can ask whoever is saying E. coli grows aerobically where their scientific data are, and I'll be happy to point out where they are missing the point.
The head of the composting program at the USDA in Beltsville visited me once and mentioned an experience where composted manure was tested and E. coli was not detected. They put the compost out into a field, and a few days later detected E. coli. This person used that example to say that E.coli can come back to life in compost.
Really? Ask the appropriate question: Were there E. coli in the field soil BEFORE they added the compost? No answer to that question when I asked it.
I have never seen that paper published either, although I must admit to not particularly looking for it. It may have gotten past reviewers who don't know much about holistic systems.
Here's another example - We take cultures of E. coli and dump them in soil. If the soil has a healthy foodweb, you will not detect E. coli in 24 hours. Ah, but if the soil is not healthy, and lacks good structure, you can detect E. coli for many days.
It's the NORMAL life that is important. If there are no competitors, no consumers, no inhibitors, then E. coli may do ok.
Think about your hands. Every time you visit the bathroom, you potentially pick up E. coli. But you aren't swarming with E. coli. Washing your hands? But that's just soap, why would that kill E. coli? You have lots and lots of bacteria and some fungi on your skin surfaces, and they compete with, inhibit and consume E .coli. Only if you are sick, and something severely disrupts the foods your skin puts out to feed the beneficial bacteria and fungi, will E. coli be able to survive, and maybe even grow.
If E. coli survived as well in aerobic conditions as it does in anaerobic, E. coli would not be useful as an indicator of human pathogens. What would kill E. coli in the real world, if it could grow just as well aerobically as it does in reduced oxygen conditions in your digestive system? E. coli would be everywhere, but it isn't.
President, Soil Foodweb Inc.
- Re: E.coli
- From: Klaus Wiegand <wiegand@LUFA-SPEYER.DE>