DNA-binding-protein inhomogeneity in E. coli modeled as biphasic facilitated diffusion

摘要

We have recently shown that nonspecifically bound lac repressors are spatially inhomogeneous in E. colincells and depends upon the location of its encoding gene and the DNA compaction state [Kuhlman and Cox,nMol. Syst. Biol. 8, 610 (2012)]. Here we model this inhomogeneity as a consequence of diffusion within andnexchange between two distinct intracellular phases: the condensed chromosomal DNA and an extrachromosomalncompartment, the cytoplasm. We discuss the consequences of this model for the target search process.