Molecular mechanisms and benefits of phenotypic heterogeneity in Sinorhizobium meliloti populations

The nitrogen-fixing symbiotic alphaproteobacterium Sinorhizobium meliloti produces exopolysaccharides (EPS) as a common good. Heterogeneity in EPS production has been observed, where a sub-population heavily engages in EPS production while other individuals vary from intermediate to absent production. Explanations for heterogeneity, both its biological significance and its molecular mechanisms are the focus of this interdisciplinary project involving experimentation and modeling approaches. We particularly investigate the role of quorum sensing in phenotypic heterogeneity of the isogenic population.