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I am novice to biochemistry and biology in general. I am reading Lehninger Principles of Biochemistry, and I found the following sentence at the beginning of the chapter on glycolysis:

A bacterium such as Escherichia coli can obtain from glucose the carbon skeletons for every amino acid, nucleotide, coenzyme, fatty acid, or other metabolic intermediate it needs for growth.

Does this mean that E. coli can survive in a medium containing H2O and glucose alone? E coli can synthesize any other nutrient it needs?

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This quote is not really true. Nitrogen is necessary for all the co-enzymes and proteins to sustain life. In order to get energy, if E coli. needs to metabolize nitogen at all as opposed to recycling it, I'd think that the bacteria would eventually all die out. –  shigeta Oct 23 '13 at 19:29
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@shigeta And where can E coli find Nitrogen, in normal conditions? I assume E coli can't synthesize Nitrogen from other atoms, since that would involve nuclear reactions! –  becko Oct 23 '13 at 19:38
    
i expanded into an answer... normally E coli live in the gut and the food we eat supplies their nitrogen (and carbohydrate) needs. Its pretty hard to find an environment on earth with no nitrogen available. –  shigeta Oct 23 '13 at 19:39
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The answer and comments about N and P are correct, but the quote is literally true - since it is restricted to a statement about carbon skeletons, not entire molecules. –  Alan Boyd Oct 23 '13 at 20:32
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@becko Also, E.coli cannot 'fix' nitrogen. That is, the organism cannot use N2 as nitrogen source. (But, as Alan Boyd has pointed out, the Lehninger quote is absolutely correct) –  TomD Oct 24 '13 at 7:42
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2 Answers

up vote 5 down vote accepted

The minimum requirement for E. coli and other bacteria to grow and survive is called minimal medium. It's even defined at Merriam-Webster:

a medium that contains only inorganic salts, a simple carbon source (as carbon dioxide or glucose), and water

Water and glucose are pretty easy, but the source of salts may often change; regardless, you really need some potassium, phosphate, and nitrogen for amino acid synthesis. This page has a bunch of information on bacterial growth, including some "recipes" for a few bacterial strains. For E. coli, the classic media is M9, which over at Sigma is made of:

  • 33.9g/L Na2HPO4 7H2O
  • 15g/L KH2PO4
  • 5g/L NH4Cl
  • 2.5g/L NaCl

Here are some other recipes.

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Yes, but no. In other words, this quote is not probably not true in the ways you'd think. Bacteria can survive on practically nothing for long periods of time, but whether you call that life is subjective.

Nitrogen is necessary for all the co-enzymes and proteins to sustain life. In order to get energy, if E coli. needs to metabolize nitrogen to waste at all, all the bacteria would eventually all die out. The same feat for human beings would be to add a little sugar into sewage and surviving on it. Nobody would die right away, but its hard to call that living maybe.

Unless a medium is exchanged, E coli in a laboratory culture will start a massive die off. When the E coli culture becomes terminal in this way, a portion of the bacteria go into stationary phases where the bacteria can survive for very long times - for months or possibly years. So some of the bacteria would survive, but they would be dormant. You might not call this survival, but tens of thousands of bacteria are still alive and can generate colonies if transferred to fresh media.

Laboratory cultures and media are of course artificial conditions which don't reflect the environment which bacteria are adapted. In their life cycle, they typically have other sorts of behavior and experience low nutrient conditions often enough. Bacteria are also different in that a 99.99% die off can be considered a typical event in some cases.

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It should also need some $P$ and I would guess other things like $Cl$ and $K$ too right? –  terdon Oct 23 '13 at 19:39
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