Predicting Growth and Finding Biomass Production Using the General Growth Mechanism

Abstract

First, we briefly describe the general growth mechanism, which governs the growth of living organisms, and its mathematical representation, the growth equation. Using the growth equation, we compute the growth curve for S. cerevisiae and show that it corresponds to available experimental data. Then, we propose a new method for finding the amount of synthesized biomass without complicated stoichiometric computations and apply this method to evaluation of biomass production by S. cerevisiae. We find that obtained results are very close to values obtained by methods of metabolic flux analysis. Since methods of metabolic flux analysis require finding produced biomass, which is one of the most important parameters affecting stoichiometric models, a priori knowledge of produced biomass can significantly improve methods of metabolic flux analysis in many aspects, which we also discuss. Besides, based on the general growth mechanism, we considered evolutionary development of S. cerevisiae and find that it is a more ancient organism than S. pombe and is apparently its direct predecessor.

Why Cells Grow and Divide? General Growth Mechanism and How it Defines Cells’ Growth, Reproduction and Metabolic Properties

“…The reduction of fraction of nutrients that goes to biomass production accordingly results in continuous irreversible changes in composition of biochemical reactions, since, as it was found in Ref. 17, this composition is tied to the amount of produced biomass. At some point, the fraction of nutrients used for biomass synthesis will reach a certain minimum value, to which a particular composition of biochemical reactions corresponds, and this triggers mitosis.…”

A Method for Modeling Growth of Organs and Transplants Based on the General Growth Law: Application to the Liver in Dogs and Humans

“…Previously, the general growth law and the growth equation have been successfully used for studying and modeling the growth and replication mechanisms in unicellular organisms, such as fission yeast and its mutants, amoeba, and S. cerevisiae [13] , [17] . Here, we propose and demonstrate a method for modeling growth of multi-cellular organs.…”

“…Usage of the fact that the maximum size of a grown multicellular organism depends on the metabolic activity of its cells is facilitated by the growth equation as follows: According to equation 5 , the increase of biomass at any given moment is proportional to the nutrient influx k , while the functional dependence of the change of nutrient influx for the same organism is similar in a wide range of growth scenarios [13] , [17] . So, once we know the minimum and maximum nutrient influxes, corresponding accordingly to the minimum and maximum metabolic rates of the cells and the minimum and maximum masses of the organism, we can find the maximum mass resulting from influx k as .…”

“…Recent studies [11][12][13][14][15][16][17] (the most important and comprehensive work is [17]), discovered that, indeed, such a regulatory mechanism exists at higher-than-molecular scales, which is called the general growth law. This law universally operates at scales ranging from cells and cellular components to organs and whole organisms.…”

“…In this arrangement, the amount of produced biomass (which in turn is defined by the growth ratio) is a leading indicator that defines composition of biochemical reactions. This fact is well studied at a cellular level [13] , [17] with the aid of methods of metabolic flux analysis. However, according to the general growth law, the same is true at the organ level.…”