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Difference between types of bacterial culture broths? - (Sep/19/2012 )

Any have any idea what each component in bacterial culture broths (Tryptone, NaCl, Yeast, KCl etc.)

Was wondering how different each broths is in terms of growth and plasmid copy numbers: LB, Millers LB, Terrific broth, SOC....

-science noob-

Tryptone is an enzymatic digest of casein used as a nitrogen source in culture media. Yeast extract is the common name for various forms of processed yeast products made by extracting the cell contents (removing the cell walls) making all cell components available to bacteria to use as food.

There is composition difference in media , some media maintains pH (Terrific broth).


Which should I use for a low copy number strain? It seems like LB doesn't yield much final plasmid content.

-science noob-

I use ZYM505 for plasmid preparation, You can grow the culture at higher densities hence more plasmid for low copy number:

even explains the different components why and when one should use them.



LBG (LB with glycerol), or any other rich broth are good for higher yield. Some plasmids are low copy number anyway - it depends on the origin of replication.