Comparative analysis of some models of mixed-substrate microbial growth
نویسنده
چکیده
Mixed-substrate microbial growth is among the most intensely studied systems in molecular microbiology. Several mathematical models have been developed to account for the genetic regulation of such systems, especially those resulting in diauxic growth. In this work, we compare the dynamics of three such models (Narang, Biotech. Bioeng., 59, 116, 1998; Thattai&Shraiman, Biophys. J, 85, 744, 2003; Brandt et al, Water Research, 38, 1004, 2004). We show that these models are dynamically similar - the initial motion of the inducible enzymes in all the models is described by Lotka-Volterra equations for competing species. The dynamic similarity occurs because in all the models, the inducible enzymes possess properties characteristic of competing species: Their synthesis is autocatalytic, and they inhibit each other. Despite this dynamic similarity, the models vary with respect to the range of dynamics captured. The Brandt et al model captures only the diauxic growth pattern, whereas the remaining two models capture both diauxic and non-diauxic growth patterns. The models also differ with respect to the mechanisms that generate the mutual inhibition between the enzymes. In the Narang model, the mutual inhibition occurs because the enzymes for each substrate enhance the dilution of the enzymes for the other substrate. In the Thattai&Shraiman model, the mutual inhibition is entirely due to competition for the phosphoryl groups.
منابع مشابه
Growth Kinetic Survey in Direct Biological Sweetening of Natural Gas in Batch Bioreactor: Temperature Studies
The present study is focused on biodesulfurization of natural gas in a batch culture using active microorganisms. The microorganisms used for the removal of hydrogen sulfide were obtained from a hot spring. The experiments were conducted with mixed gas at operating temperatures of 25 to 45°C with a time interval of 5h. Two kinetic models included Logistic and Monod models in a batch culture wer...
متن کاملComparative investigation on the correction factors of hydrogen permeability on CNTs-Mixed matrix membrane
This paper discusses different important gas permeation models such as “Maxwell”, “Bruggeman”, “Lewis-Neilson”, and “Pal” models to predict “Mixed Matrix Membranes” (MMMs) performance. The main parameter considered and discussed is the permeability of Hydrogen on Carbon Nanotubes (CNTs)-MMM. For evaluation of the theoretical models, experimental data of permeability for H2 were compa...
متن کاملComparative investigation on the correction factors of hydrogen permeability on CNTs-Mixed matrix membrane
This paper discusses different important gas permeation models such as “Maxwell”, “Bruggeman”, “Lewis-Neilson”, and “Pal” models to predict “Mixed Matrix Membranes” (MMMs) performance. The main parameter considered and discussed is the permeability of Hydrogen on Carbon Nanotubes (CNTs)-MMM. For evaluation of the theoretical models, experimental data of permeability for H2 were compa...
متن کاملTowards an Integrated Physiological Theory of Microbial Growth: from Subcellular Variables to Population Dynamics
The dynamics of microbial growth is a problem of fundamental interest in microbiology, microbial ecology, and biotechnology. The pioneering work of Jacob Monod, served as a starting point for developing a wealth of mathematical models that address different aspects of microbial growth in batch and continuous cultures. A number of phenomenological models have appeared in the literature over the ...
متن کاملComparison of Conduction Based and Mediator Based Models for Microbial Fuel Cells
Microbial fuel cells (MFCs) are processes used for simultanuous bioenergy capturing and waste treatment. In this study, a model for MFCs based upon a conduction mechanism for electron transfer is proposed, which integrates substrate utilization, current production and conduction and microbial distribution and growth in batch flow mode. The outputs of the model and that of a mediator based mode...
متن کامل