LB media chemical composition
scott.coutts at med.monash.edu.au
Thu Feb 12 21:08:03 EST 2004
Oops, I hit the 'send' button too quickly on the other post and forgot
to add a few things...
> What is the chemical composition of LB media? The product sheets
> generally list the "ingredients" as tryptone and yeast extract, and some
> list the composition in terms of amino acids and electrolytes. But it
> appears that given its messy origins this LB should be quite a bit more
> rich with metabolites.
You only get the list of amino acids and electrolytes because,
generally, that's all we care about for non-fastidious organisms.
> For example does LB contain nitrogenous bases or
> nucleotides? What carbohydrates are known to be present?
The nucleotide products may be present in the yeast extract, but they
are not added in any other form. Most of the nitrogen requirements of
the organisms are satisfied by the amino acids in the trypton.
To find out what carbohydrates are present, you'll have to look for th
echemical analysis of the yeast extract and tryptone. There are no
extra, particular carbohydrates added. Remember that the bacteria that
grow on LB are quite capable of syntesising their own metabolites.
By the way, you'll probably find analysis sheets from Oxoid's website,
so you can look up the yeast extract and tryptone.
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