Research Topic: Metabolic Heterogeneity
Population variation
Populations of genetically identical bacteria have historically been assumed to behave in the same way. But there is emerging evidence that phenotypic heterogeneity is widespread in nature. A small proportion of cells may undertake a metabolic strategies that are distinct from the majority. This may be an adaptive bet-hedging strategy - allowing these cells to be poised to rapidly grow in response to fluctuating environmental conditions.
New analytical techniques
We are addressing phenotypic heterogeneity with new analytical approaches, primarily using secondary ion mass spectrometry (SIMS). The SIMS instrument at Washington University has unique capabilities than make it particularly well-suited to the analysis of microbial populations, using elemental or isotopic labeling techniques.
Hundreds of cells, one-by-one
By combining careful growth of microbial cultures, stable isotope probing, and SIMS, we can interrogate the metabolic phenotype of hundreds of individual cells, and look for differences in individual cells. We are developing new techniques to measure phenotypic heterogeneity, performing experiments to understand its underlying mechanisms, and to understand when it is adaptive in populations.
(Figure from McClelland et al., 2020)