1
$\begingroup$

I am creating a mathematical model for the growth of Synechocystis. sp PCC 6803 and Methanosarcina barkeri Fusaro in photobioreactors and anaerobic membrane bioreactors respectively. I have a couple of questions regarding this:

  1. When you buy these strains, or bacteria in general, from a supplier, how many bacteria will you receive? (I need this for the initial number of bacteria)
  2. How do you find/calculate the half-saturation constant? (Used in Monod's equation)
  3. How do you find/calculate the growth limiting substrate? (Used in Monod's equation)

Any help would be appreciated!

$\endgroup$
  • $\begingroup$ What are your thoughts on questions 2 and 3? We can't really help you if you haven't even tried to answer these questions by yourself... $\endgroup$ – Flo Mar 9 '17 at 9:40
1
$\begingroup$
  1. When you buy these strains, or bacteria in general, from a supplier, how many bacteria will you receive? (I need this for the initial number of bacteria)

You don't know how many cells you'll get. Depending on the strain and on how it was preserved (frozen, freeze-dried, liquid culture), the percentage of viable cells in the sample you get can vary a lot. Anyway, it is not like this that you will find the initial number of bacteria for your model. Before inoculating your bioreactors, pre-cultures have to be prepared. You won't be directly using the supplier's sample as inoculum.

As for how to determine the cell count in your pre-culture, it really depends on what kind of equipment you have access to. If you have access to a flow cytometer, then you can get the cell count directly. Otherwise, you can use more "traditional" microbiological techniques (Optical density, Petri dishes, Dry weight ...).

You might even consider using another variable than cell number for your growth model. It is often the optical density or the dry wheight that is modelled, rather than the number of cells.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.