1. Dynamics of Snake-like Swarming Behavior of Vibrio alginolyticus
Thomas Böttcher, Hunter L. Elliott, Jon Clardy 
Biophysical Journal 
Volume 110, Issue 4, Pages (February 2016)
DOI: /j.bpj
Copyright © 2016 Biophysical Society Terms and Conditions

2. Figure 1
Swarming of V. alginolyticus B522 on carrageenan with three magnifications: colony-swarming pattern on a plate with the coordinate system used in this study (10 mm), live cell imaging of the swarming front (6 μm), and TEM electron micrographs of cells with polar (P) and lateral (L) flagella (1 μm and 500 nm).
Biophysical Journal  , DOI: ( /j.bpj )
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3. Figure 2
Motion analysis of the swarming front. (A) Phase-contrast image of the swarming front is shown at the start of the time-lapse image series. (B) Whole-image-series temporal variance analysis indicates patches of different intense motion activity: high variance (red) and low variance (blue). (C) The fraction of time with significant variance analysis reveals decreasing motion toward the swarming front: large fraction of time with significant variance (red) and small fraction of time with significant variance (blue). (D) The fraction of pixels with significant variance is plotted against the distance from the front averaged from three independent replicates. To see this figure in color, go online.
Biophysical Journal  , DOI: ( /j.bpj )
Copyright © 2016 Biophysical Society Terms and Conditions

4. Figure 3
Advancement of the swarming front: (A) overlay of the advancement of the front during 2.5 min and (B) the corresponding distance in μm advanced for different regions along the front. The (C) protrusion (cell highlighted) and (D) pushing modes of expansion of the natural swarming front over time and lateral sliding of cells at the front are shown. To see this figure in color, go online.
Biophysical Journal  , DOI: ( /j.bpj )
Copyright © 2016 Biophysical Society Terms and Conditions

5. Figure 4
Swarming in the x- and z-dimensions. (A) The mean temporal variance changes with the distance from the swarming front differently for surface and bottom layer. (B) Depth (thickness) of the cell layer is measured from the surface versus distance from the swarming front. Whole-image-series temporal variance analysis heat maps show different swarming phases: (C) close to the swarming front, (D) at ∼500 μm distance to the front, and (E) in the top layer at 2.3 mm distance to the front. In all images the spatial coverage by cells is 100%. (F) Only a thin layer at the bottom around 40 μm from the surface of the mature colony is motile (high temporal variance), whereas the surface is stationary. To see this figure in color, go online.
Biophysical Journal  , DOI: ( /j.bpj )
Copyright © 2016 Biophysical Society Terms and Conditions

6. Figure 5
(A) The fraction of time with significant variance analysis of cells at ∼1000 μm distance from the swarming front and, for comparison, (B) the fraction of time with significant variance analysis in phase 1, corresponding to Fig. 4 C. (C) Overlay of whole-image-series temporal variance analysis (red) of cells in late phase 2 with phase-contrast images (gray) is shown. Movement in the z-dimension can be inferred from real-time microscopy and the overlapping of cells. Motion is restricted mainly to foci at the tips of cells, whereas motion of cells in phase 1 (D) is confined to the xy-dimension. To see this figure in color, go online.
Biophysical Journal  , DOI: ( /j.bpj )
Copyright © 2016 Biophysical Society Terms and Conditions

7. Figure 6
(A) Swarming morphology of different strains of V. alginolyticus on NBE carrageenan plates (scale bar, 10 mm), with the top half of the swarming edge highlighted by a dashed line. (B) Phase-contrast image of the swarming front of the slow-swarming strain V. alginolyticus ATCC highly elongated cells and a lack of a clearly defined front is shown at the start of the time-lapse image series. (C) Whole-image-series temporal variance analysis indicates only low-motion activity compared with fast swarmers. To see this figure in color, go online.
Biophysical Journal  , DOI: ( /j.bpj )
Copyright © 2016 Biophysical Society Terms and Conditions

8. Figure 7
Model of a swarming colony: (1) swarming front, (2) phase of reduced motion, (3) motion increases in z-dimension, (4) new layers of highly motile cells form underneath the original layers, and (5) motion of cells on the surface layer sharply decreases with increasing thickness until static. Bacteria are able to freely move between the layers as indicated in the model.
Biophysical Journal  , DOI: ( /j.bpj )
Copyright © 2016 Biophysical Society Terms and Conditions