can bacteria grow on agar? - (Sep/24/2008 )
Hello,
I want to test if bacteria can grow on certain carbon source on agar plate. Anyone know if agar can be utilized as nutrition?
Thank you!
I guess so, as bugs can grow on pretty much anything, but their growth will probably be severely limited, as they will not have many other micronutrients like metals etc. Why not try it and see? Melt up some agar, as well as agar plus nutrients (ie LB), plate out some cells and let us know. 
Never say never, but as far as I am aware agar was introduced because it is not utilised by microbes like gelatine or other gelling compounds. But I think you should include some water agar (ultrapure water with agar) as control in your experiment. If your bugs grow there you will have to think of something else.
But why do you want to use agar plates and not liquid culture media? you could measure the growth rate with the OD of your medium or use something like the biolog system (example is for gram negative bacteria)?
I really know for sure about marine bacteria isolated from sea water, they can really grow on agar agar. Soil bacteria are also very versatile, but I haven't seen any to degrade agar.
Would have been so obvious
: agar-agar derived from alge *slap my head*! Thanks for the information, you do not by chance have some citation for this?? I want to test if bacteria can grow on certain carbon source on agar plate. Anyone know if agar can be utilized as nutrition?
Thank you!
I'd also say never say never, but as long as they don't have the proper enzymes to disconstruct the galactose-chains, they won't get to the galactose and furthermore must be able to utilise galactose as a glucose or fructose donor.. If you can exclude that, you can be sure they won't grow. Perhaps do some research about the galactose utilization genes of your bacteria strain.
I'd say that e.coli can't do that since I never observed on "forgotten" (and therefore incubated for some... lets say days
) plates any agar lysis, but as soon as you work with rather exotic bacteria strains, you can't be sure. Nah i really doubt common bacteria will grow on this kinda media..
u need some kinda exotic bacteria that's probably associated with algae?! or whatever the source of that agar-agar..
u need some kinda exotic bacteria that's probably associated with algae?! or whatever the source of that agar-agar..
Agar alone I have never seen used, agar based nutrient growt plates yes (LB-agar, blood agar,...), but the bacteria just uses tha nutrients within the plate and leave the agar structure alone.