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OD range for spreading on agar - (Aug/23/2012 )

Hi all,

I want to resuspend colonies from a mixed culture (environmental, no strains) that I have on a plate (M9 agar) and respread it on a new plate to do a little comparison on how well they will grow on different solid media. Problem is I am not sure how much (both in volume and OD) would normally be ok for spreading on a plate in order to avoid a mess of growth or an empty plate. Is there a range of "suitable" ODs for plating?

Thanks in advance,
Omni

-Omnimax-

OD 1 is very approximately 10^9 cells/ml (varying a lot by species and medium, and phase of moon). You probably don't want more than a thousand cells on your plate, so you want to dilute 10^5 (adjust for measured OD) and then plate 100 ul. You'll likely hit the right place if you did this with 10^4, 10^5, and 10^6 dilutions of an OD 1 culture.

-phage434-

Thanks a lot! I'll try this tomorrow and see how it works out.

-Omnimax-

THe use of OD is something that is being misused by many.
I would advise you to check the attachements.
Try to understand it , if you do, it will make everything a lot easier and you would not make mistakes like so many others (even in published papers) do.
Attached File

Attached File

-pito-

phage434 on Thu Aug 23 16:13:15 2012 said:


OD 1 is very approximately 10^9 cells/ml (varying a lot by species and medium, and phase of moon). You probably don't want more than a thousand cells on your plate, so you want to dilute 10^5 (adjust for measured OD) and then plate 100 ul. You'll likely hit the right place if you did this with 10^4, 10^5, and 10^6 dilutions of an OD 1 culture.


Phase of moon?
uh?

-lyok-

Phase of moon indicating unknown factors that are affecting your experiment. A joke. I hope.

-phage434-