1. Chemotaxis by Vibrio corallyticus in coral mucus

2. Basic set up Coral mucus interface data Figure 1. (a) The observation viewing chamber created using cover slips. The dashed rectangles indicate the transect positions (b) is a close up schematic of the transect line and individual quadrats, which were 2408 µm and 172 µm in length respectively. (c) Micrographs of the culture, interface and mucus. The diffraction rings indicate particulate matter in the mucus. Scale bar = 20 µm.

3. Figure 2. The average numbers of search patterns identified across a culture media to mucus interface. The solid line represents the 3-step flick search patterns, the dashed line represents the run and reverse search patterns and the dotted line represents the straight swimming search patterns.

4. Figure 3. The mean search pattern speeds identified across a culture media to mucus interface. The solid line depicts three-step flick search patterns, the dashed line depicts run and reverse search patterns and the dotted line depicts straight swimming search patterns.

5. Figure 4. The mean search pattern speeds identified in solutions of various viscosity (cP). The solid line depicts flick search patterns, the dashed line depicts run and reverse search patterns and the dotted line depicts straight swimming search patterns.

6. DMSP and coral mucus data Figure 1. The flaA and flhA gene expression values in chemoattractant experiments, (a) gene copies/ ng RNA across various DMSP concentrations, (b) gene copies/ ng RNA across the various coral mucus additions

7. Figure 5. The energy requirements for V. coralliilyticus in solutions of differing viscosities during (a) 3- step flick search patterns, (b) straight swimming search patterns and (c) run and reverse search patterns.

8. Energy expenditure Energy expenditure of motility in viscous conditions Figure. Chemotactic search patterns speed variance from the seawater to coral mucus with a viscosity increase from 1 cP in the seawater region to 2.3 cP in the mucus region. Error bars = SEM. Circles and a solid line represents flicks, squares and a dashed line represents run-reverses and triangles and a dotted line represent straight swims.

9. (a) seawater mucus (b) Glucose molecules (s- 1 ) seawater mucus Figure. (a) The cost, in glucose molecules s -1, experienced by V. coralliilyticus in utilizing the three common chemotactic search patterns across a seawater to coral mucus interface identifying how the cost of motility increases with increasing viscosity experienced by cells when moving into the mucus region surrounding the coral tissue surface. A trend line is plotted through the majority of the data with a R 2 value of 0.9945. The final data point is not included in the trend line as it presents as an outlier which may be an effect from the mucus region; (b) The cost, in glucose molecules s -1, experienced by V. coralliilyticus in utilizing the three common chemotactic search patterns across a seawater to coral mucus interface identifying how the cost of motility increases when cells move into the mucus region surrounding the coral tissue surface. In both figures, circles and a solid line present flicks, squares and a dashed line represents run-reverses and triangles and a dotted line represent straight swims.

10. (b) Diffusivity seawater mucus (a) Figure. (a) The diffusivity values of utilized chemotactic search patterns of varied run times (in seconds) across a seawater to coral mucus interface which increases in viscosity from l-r. Squares represent run-reverses, triangles represent flicks, circles represent straight swims. The solid shapes represent run times of 0.2 s, and the open shaped represents run times of 1.4 s. The diamond shape represent 0.8 s straight swim run times; (b) The DMSP diffusivity values calculated with V. coralliilyticus’s three prominent chemotactic search patterns compared to the cost involved (in glucose molecules) of maintaining the diffusivity values. Circles represent flicks, squares represent run-reverses and triangles represent straight swims.

11. seawater mucus (a) (b) Flux Figure. (a) The flux of DMSP variance across a seawater to coral mucus interface; (b) The flux of DMSP concentration values associated with the cost, in glucose molecules s -1 required. Circles and the solid line represents flicks, squares and a dashed line represents run- reverses and triangles and a dotted line represents straight swims.

14. Bouslimani et al. PNAS 2015