Fig. 2: Nitrogen and sulfur metabolism in R2 before coupling.

Relative abundances of genes encoding enzymes in (a) nitrogen metabolic pathway and (b) sulfur metabolic pathway in R2 before coupling. The data were referenced from the KEGG database based on the 16S rRNA gene amplicon sequencing data. The relative abundances of genes were determined by normalizing the gene concentrations and comparing them by using targeted reads per million mapped reads (rpmr).