Show simple item record

dc.contributor.authorPrats Soler, Clara
dc.contributor.authorGiró Roca, Antoni
dc.contributor.authorFerrer Savall, Jordi
dc.contributor.authorLópez Codina, Daniel
dc.contributor.authorVives-Rego, J
dc.contributor.otherUniversitat Politècnica de Catalunya. Departament de Física i Enginyeria Nuclear
dc.identifier.citationPrats, C. [et al.]. Analysis and IbM simulation of the stages in bacterial lag phase: basis for an updated definition. "Journal of theoretical biology", Maig 2008, vol. 252, núm. 1, p. 56-68.
dc.description.abstractThe lag phase is the initial phase of a culture that precedes exponential growth and occurs when the conditions of the culture medium differ from the pre-inoculation conditions. It is usually defined by means of cell density because the number of individuals remains approximately constant or slowly increases, and it is quantified with the lag parameter l. The lag phase has been studied through mathematical modelling and by means of specific experiments. In recent years, Individual-based Modelling (IbM) has provided helpful insights into lag phase studies. In this paper, the definition of lag phase is thoroughly examined. Evolution of the total biomass and the total number of bacteria during lag phase is tackled separately. The lag phase lasts until the culture reaches a maximum growth rate both in biomass and cell density. Once in the exponential phase, both rates are constant over time and equal to each other. Both evolutions are split into an initial phase and a transition phase, according to their growth rates. A population-level mathematical model is presented to describe the transitional phase in cell density. INDividual DIScrete SIMulation (INDISIM) is used to check the outcomes of this analysis. Simulations allow the separate study of the evolution of cell density and total biomass in a batch culture, they provide a depiction of different observed cases in lag evolution at the individual-cell level, and are used to test the population-level model. The results show that the geometrical lag parameter l is not appropriate as a universal definition for the lag phase. Moreover, the lag phase cannot be characterized by a single parameter. For the studied cases, the lag phases of both the total biomass and the population are required to fully characterize the evolution of bacterial cultures. The results presented prove once more that the lag phase is a complex process that requires a more complete definition. This will be possible only after the phenomena governing the population dynamics at an individual level of description, and occurring during the lag and exponential growth phases, are well understood.
dc.format.extent13 p.
dc.subjectÀrees temàtiques de la UPC::Enginyeria agroalimentària::Enginyeria del medi rural
dc.subjectÀrees temàtiques de la UPC::Enginyeria agroalimentària::Ciències de la terra i de la vida::Microbiologia
dc.subject.lcshMathematical modelling--theory and applications
dc.subject.otherMathematical model Cell density growth rate Biomass growth rate System dynamics Transient processes
dc.titleAnalysis and IbM simulation of the stages in bacterial lag phase: basis for an updated definition
dc.subject.lemacModels matemàtics
dc.subject.lemacBiomassa -- Congressos
dc.contributor.groupUniversitat Politècnica de Catalunya. SC-SIMBIO - Sistemes complexos. Simulació discreta de materials i de sistemes biològics
dc.rights.accessRestricted access - publisher's policy
dc.description.versionPostprint (published version)
upcommons.citation.authorPrats, C.; Giro, A.; Ferrer, J.; Lopez, D.; Vives-Rego, J.
upcommons.citation.publicationNameJournal of theoretical biology

Files in this item


This item appears in the following Collection(s)

Show simple item record

All rights reserved. This work is protected by the corresponding intellectual and industrial property rights. Without prejudice to any existing legal exemptions, reproduction, distribution, public communication or transformation of this work are prohibited without permission of the copyright holder