Fig. 1: Quantification of alkaline phosphatase gene expression in the ocean.

The samples were grouped by depth: surface (SRF; n = 103), deep chlorophyll maximum (DCM; n = 49) and mesopelagic (MES; n = 26). A The figure shows the normalized transcript abundances of alkaline phosphatase families across major taxonomic groups in the Tara Oceans dataset. ‘other’ refers to taxa that were not classified within the highlighted groups. B Total normalized transcript abundance50 from each alkaline phosphatase family across all samples and depth layers. Letters above the bars denote statistically significant differences determined by pairwise two-sided Mann-Whitney U tests (p < 0.05). Groups that do not share a letter are significantly different from one another. In the box plots, the center line represents the median, box limits indicate the interquartile range (IQR), whiskers extend to 1.5× the IQR, and points beyond the whiskers are individual data points.