If I take E. coli (DH5A for example) and grow it on LB the growth curve will be the classic we all know, with mid exponential phase ~2-4h.
How will it look if I grow it on minimal defined media such as M9?
Here are some guiding questions:
A. Will it reach the same final density?
B. Will it take longer to reach the exponential phase (longer lag phase), how much longer?
C. will the exponential growth be slower (generation time longer)? How much?
I can guess at these but I wonder if anyone here ever ACTUALLY done it and can help me plan my time.
Added a picture of what google could tell me, but the resolution is not good (measuring every 1 hour) and a picture of a classic growth curve
CREDIT:
Pic 1 - http://2013.igem.org/Team:Imperial_College/Growth_Assays
Pic 2 - https://openi.nlm.nih.gov/detailedresult.php?img=PMC4556300_ijn-10-179Fig2&req=4
OK, I went ahead and did this, so for people reading this in the future:
1. After 24 hours it does not reach the same density. The LB culture got to 1.5-1.9 OD, and the M9 culture to 1.1-1.2
2. The lag phase is longer, it takes more than 6 hours for the bacteria to adapt to the M9 and reach exponential phase. The LB culture took 2h30m to reach roughly mid exponential phase
3. I could not measure the generation time because after 6 hours I stopped measuring, only to take the next point the next day. After 6 it looked like the beginning of the exponential phase
Bottom line:
The lag phase is much longer and the bacteria don't reach the same density after 24 hours. But they can grow.
Technical notes:
- I used 2 E. coli strains (DSM 9031, 3871), grown first on LB plates and then transferred to liquid culture
- I only did this once (so far)
- The M9 was made according to a standard protocol, I used glucose as the carbon source. (https://uk.vwr.com/assetsvc/asset/en_GB/id/18501639/contents)
Hello,
I always do that, the only difference is the growth speed . You will reach OD. 0.6 in LB within 3h. however, in the minimal media M9, to have the same OD it takes at least 6 to 7 hours of growth . You will have the classic shaped growth curve
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