A quantitative study of gene regulatory pathways in Bacillus subtilis for virulence and competence phenotype by quorum sensing

Abstract

Quorum sensing (QS) is a process which allows a population of bacteria to coordinately regulate gene expression of their entire community. Bacillus subtilis is a soil organism which uses QS to alternate between competence for DNA uptake and sporulation. We propose a model to describe the components involved in QS and to analyze reaction species involved in the regulation of QS machinery. We targeted only those QS phenotypes for which the genetic organization and molecular characterization of the components are fully elucidated. We have analyzed simulations for concentration of different species involved in competence as well as sporulation pathways at diverse time period using quantitative methods. It was observed that there is possibility of achieving different measurement from reactions taken place between species by applying irreversible Michaelis–Menten kinetic law. We obtain variation in measurement on changing parameters such as concentrations ranging from 0.3 to 50 lM in stepwise manner by setting end time in the range of 0.1–100 ms.