Fig. 4: Regression analyses of phosphorus-cycling genes in regions of the global ocean with varying phosphate concentrations.
From: Timing the evolution of phosphorus-cycling enzymes through geological time using phylogenomics
The abundance of reads encoding part of pstS, nptA, phnJ and phnM are plotted on the y-axis against micromolar phosphate concentrations on the x-axis, for all 139 samples from the Ocean Microbial Reference Catalogue v2 (OM-RGC.v2) of the Tara Oceans Project44,45. Regression lines are shown in red and represent the results of two-sided tests. The resulting p values are <2.2 × 10−16 for pstS and nptA, 4.5 × 10−8 for phnJ and 8.2 × 10−9 for phnM with 129 degrees of freedom. Grey areas indicate low phosphate concentrations where the abundances of CP-lyase genes are particularly high.
