Modeling cell populations metabolism and competition under maximum power constraints
Fig 2
Self-regulating cell population system.
The diagram in (A) represents a self-regulating cell population seen as a system that produces and consumes ATP from primary energy and microenvironmental resources, respectively through the processes of ATP production and biosynthesis. The cells stock exerts feedback on the ATP production process needed for proliferation. From the biosynthesis process develops feedback on growth represented by the population’s ability to: 1) regulate limiting factors coming from the interaction with the micro-environment, as cofactors and dissolved ions; 2) produce functional proteins, molecular machines and enzymes that enable reactions and control their rates. From (A) we define in (B) the modeled quantities: the primary energy inflow, Jin; the ATP production efficiencies, η; the cells stock Q that grows according to with P(Q) = ηJin = rQ·(1−Q/K), net power inflow (with r intrinsic growth rate, K carrying capacity), and R(Q) = Q/τ energy outflow, being τ the proteome turnover time; the stock of resources, N = K−Q, for the mass balance to hold; the total heat flow Jh = P/η = Jin in steady state.