Part 4: Substrate turnover Flashcards
What is Michaelis & Menten (1913) theory?
Substrate turnover by an enzyme is dependant on the concentration of the turnover. Vs = δs/δt.
What is the Monod (1949) theory?
Microbial growth is dependant on substrate turnover.
How are half saturation and half growth coefficients (Ks and Km) determined?
Experimentally, using y=mx+c
What is the term for a bacteria that is more efficient at low substrate concentrations?
Oligocarbophilic
What is the term for a bacteria that is more efficient at high substrate concentrations?
Copiotrophic.
Which type of organism can be expected to be enriched by using standard microbiological media?
Copiotrophic bacteria, since these are more efficient at high substrate concentrations.
In what way are copiotrophic bacteria “opportunistic”?
Copiotrophs can remain viable for long periods of time without a substrate, and then respond rapidly when nutrients become available.
Why is Ks not always appropriate for determining competition between organisms?
Testing has shown that substrate copiotrophs can sometimes outcompete oligocarbophiles even with a higher Ks value. Shows that Ks is not always effective.
What is the affinity constant, Vs^o?
The affinity constant represents the substrate turnover when S approaches zero. i.e. the gradient of the curve at S=0.
What is a continuous culture?
Adding small amount of microbiological medium over time to replicate natural conditions.
