Fig. 3

Identifying the major sites of metabolic activity during infection. Pocillopora damicornis was infected with ¹⁵N-labeled Vibrio coralliitycus and fixed at 2.5, 6 and 22 h post-inoculation. NanoSIMS images were taken of each polyp and a standardised scale (0 to 4000) was applied to the resulting ¹⁵N/¹⁴N images. The software L’IMAGE was used to draw regions of interest around tissue layers and ¹⁵N-hotspots (where δ¹⁵N > 300, size > 10 pixels). a Mean δ¹⁵N in four tissues: the oral epidermis (red), the oral gastrodermis (blue), the aboral gastrodermis (black), and the mesenterial filaments (green). b Mean hotspot density in the same four tissues, relative to the area of the tissue imaged. Values represent mean ± S.E.M, n = 5-14 images, per tissue per coral fragment (n = 73 images in total)