Microfluidic Confinement of Single Cells of Bacteria in Small Volumes Initiates High-Density Behavior of Quorum Sensing and Growth and Reveals Its Variability

Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, IL 60637, USA.
Angewandte Chemie International Edition (Impact Factor: 11.26). 07/2009; 48(32):5908-11. DOI: 10.1002/anie.200901550
Source: PubMed


One is a quorum: As few as one to three cells of Pseudomonas aeruginosa bacteria are confined in small volumes by the use of microfluidics. These small numbers of cells are able to activate quorum sensing (QS) pathways and achieve QS-dependent growth. The results also show that at low numbers of cells, initiation of QS is highly variable within a clonal population.

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    Acta Biomaterialia 03/2015; 18. DOI:10.1016/j.actbio.2015.02.028 · 6.03 Impact Factor
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    • "Other studies addressed the optimal density at which QS is predicted to become advantageous (Pai & You, 2009). In microfluidic devices, confinement was shown to induce a QS response even for single cells (Boedicker et al., 2009). Spatiotemporal activation of cells has been modelled by Dilanji et al. (2012). "
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    FEMS Microbiology Letters 01/2014; 352(2). DOI:10.1111/1574-6968.12394 · 2.12 Impact Factor
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    • "However, in most microdevices, the target cells are eukaryotic, such as mammalian cells and yeasts (Sims and Allbritton, 2007; Gupta et al., 2010, Lindstrom and Andersson-Svahn, 2010), because their size, a few millimeters to tens of micrometers, allows for easy handling compared to bacteria, which are much smaller in size. Thus far, only a few studies have used microdevices for single bacterial cell analysis (Balaban et al., 2004; Cai et al., 2006, Ottesen et al., 2006; Weibel et al., 2007, Boedicker et al., 2009; Teng et al., 2013, Wakamoto et al., 2013). In addition, in many microdevices that are based on microfluidic channels and valves or droplets generated in a microfluidic channel, the closed nature of the system makes the collection of cells from the device and their subsequent use difficult. "
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