Modelling conjugation with stochastic differential equations

JOURNAL OF THEORETICAL BIOLOGY

卷:263

Article

Philipsen, K. R.¹  Christiansen, L. E.¹  Hasman, H.²  Madsen, H.¹ 

[1] Tech Univ Denmark, DTU Informat, DK-2800 Lyngby, Denmark

[2] Tech Univ Denmark, Natl Food Inst, DK-1790 Copenhagen V, Denmark

关键词: SDE;    Horizontal gene transfer;    Resistance;    CTSM;    Enterococcus faecium;    Mathematical modelling;    Hidden Markov model;    Likelihood-ratio test;    AIC;   

DOI  :  10.1016/j.jtbi.2009.11.011

来源: Elsevier

【 摘 要 】

Conjugation is an important mechanism involved in the transfer of resistance between bacteria. In this article a stochastic differential equation based model consisting of a continuous time state equation and a discrete time measurement equation is introduced to model growth and conjugation of two Enterococcus faecium strains in a rich exhaustible media. The model contains a new expression for a substrate dependent conjugation rate. A maximum likelihood based method is used to estimate the model parameters. Different models including different noise structure for the system and observations are compared using a likelihood-ratio test and Akaike's information criterion. Experiments indicating conjugation on the agar plates selecting for transconjugants motivates the introduction of an extended model, for which conjugation on the agar plate is described in the measurement equation. This model is compared to the model without plate conjugation. The modelling approach described in this article can be applied generally when modelling dynamical systems. (C) 2009 Elsevier Ltd. All rights reserved.

【 授权许可】

Free