title: A mesoscopic stochastic model for the specific consumption rate in substrate-limited microbial growth.
abstract: The specific consumption rate of substrate, as well as the associated specific growth rate, is an essential parameter in the mathematical description of substrate-limited microbial growth. In this paper we develop a completely new kinetic model of substrate transport, based on recent knowledge on the structural biology of transport proteins, which correctly describes very accurate experimental results at near-zero substrate concentration values found in the literature, where the widespread Michaelis-Menten model fails. Additionally, our model converges asymptotically to Michaelis-Menten predictions as substrate concentration increases. Instead of the single active site enzymatic reaction of Michaelis-Menten type, the proposed model assumes a multi-site kinetics, simplified as an apparent all-or-none mechanism for the transport, which is controlled by means of the local substrate concentration in the close vicinity of the transport protein. Besides, the model also assumes that this local concentration is not equal to the mean substrate concentration experimentally determined in the culture medium. Instead, we propose that it fluctuates with a mostly exponential distribution of Weibull type.
authors.affiliation: Grupo de Sistemas Complejos, Universidad Politécnica de Madrid (UPM), av. Puerta de Hierro, 2 - 4, 28040 Madrid, Spain.|CEI Campus Moncloa, UCM-UPM, Madrid, Spain.
authors.forename: F J
authors.identifier: http://orcid.org/0000-0003-1270-0701
authors.initials: FJ
authors.lastname: Arranz
authors.affiliation: Departamento de Microbiología III, Facultad de Biología, Universidad Complutense de Madrid (UCM), c. José Antonio Nováis, 2, 28040 Madrid, Spain.|CEI Campus Moncloa, UCM-UPM, Madrid, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Peinado
mesh_terms: D001419:Bacteria / Q000254:growth & development / Q000378:metabolism*; D018407:Bacterial Physiological Phenomena; D050260:Carbohydrate Metabolism; D049109:Cell Proliferation; D008962:Models, Theoretical; D013269:Stochastic Processes