Single-cell responses to environmental cues
Clonal microbial populations feature cell-to-cell differences in physiological parameters such as gene expression, growth rate, and resistance to stress [1,2]. This phenotypic heterogeneity is at the basis of fundamental biological processes such as membrane transport, stem cell differentiation, and tolerance to antimicrobial compounds. Therefore, it is paramount understanding how changes in the environment affect the phenotypic heterogeneity within a clonal microbial population.
In this talk I will illustrate how embryonic stem cells respond to physical environmental cues such as transient confinement into narrow grooves. I will show that their mechanical response is heterogeneous and, remarkably, that the nuclei of some embryonic stem cells display a unique material property that is they are auxetic; exhibiting a cross-sectional expansion when stretched and a cross-sectional contraction when compressed .
I will then talk about the different strategies that individual bacteria can exploit to escape antibiotics and illustrate current efforts to understand how the environment predetermines the outcome of antibiotic treatment. Specifically, I will present a novel approach, based on microfluidics and time-lapse imaging, for simultaneously investigating the physiological response to drugs of thousands individual bacteria, including rare antibiotic tolerant phenotypes . I will then conclude by presenting some of our latest experimental and theoretical efforts to rationalise antibiotic accumulation in single gram-negative bacteria which is paramount for tackling the current antimicrobial resistance crisis .
 Lidstrom & Konopka Nature Chemical Biology 6, 705 (2010).
 Ackermann, Nature Reviews Microbiology 13, 497 (2015).
 Pagliara et al., Nature materials 13, 638 (2014).
 Bamford et al., BMC Biology 15, 121 (2017).
 Cama et al., Biorxiv, https://www.biorxiv.org/content/10.1101/645507v1.
This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..