Observation of content and heterogeneity of poly-β-hydroxybutyric acid (PHB) in Legionella bozemanii by vibrational spectroscopy

Information on how cells respond to their environment, interact with each other, or undergo complex processes such as cellular differentiation or gene expression has been obtained mostly by interference from population-level data. Individual microorganisms, even those on supposedly "clonal" populations, may differ widely from each other in terms of their genetic composition, physiology, biochemistry, or behaviours. This genetic and phenotypic heterogeneity has important practical consequences for a number of relevant interests, including antibiotic or biocide resistance, the productivity and stability of industrial fermentations, the efficacy of food preservatives, and the potential of pathogens to cause disease. Here we introduce vibrational spectroscopy to characterize Legionella bozemanii with respect to its content of poly-hydroxybutyric acid (PHB) and its distribution on both the population level and the single cell level.