@article{2679,
  keywords = {Models, Biological, Myxococcus xanthus},
  author = {Shashi Thutupalli and Mingzhai Sun and Filiz Bunyak and Kannappan Palaniappan and Joshua Shaevitz},
  title = {Directional reversals enable Myxococcus xanthus cells to produce collective one-dimensional streams during fruiting-body formation.},
  abstract = { <p>The formation of a collectively moving group benefits individuals within a population in a variety of ways. The surface-dwelling bacterium Myxococcus xanthus forms dynamic collective groups both to feed on prey and to aggregate during times of starvation. The latter behaviour, termed fruiting-body formation, involves a complex, coordinated series of density changes that ultimately lead to three-dimensional aggregates comprising hundreds of thousands of cells and spores. How a loose, two-dimensional sheet of motile cells produces a fixed aggregate has remained a mystery as current models of aggregation are either inconsistent with experimental data or ultimately predict unstable structures that do not remain fixed in space. Here, we use high-resolution microscopy and computer vision software to spatio-temporally track the motion of thousands of individuals during the initial stages of fruiting-body formation. We find that cells undergo a phase transition from exploratory flocking, in which unstable cell groups move rapidly and coherently over long distances, to a reversal-mediated localization into one-dimensional growing streams that are inherently stable in space. These observations identify a new phase of active collective behaviour and answer a long-standing open question in Myxococcus development by describing how motile cell groups can remain statistically fixed in a spatial location.</p> },
  year = {2015},
  journal = {J R Soc Interface},
  volume = {12},
  pages = {20150049},
  month = {2015 Aug 06},
  issn = {1742-5662},
  doi = {10.1098/rsif.2015.0049},
  language = {eng},
}