FIG 6.

(a) Frequency of reads for genes of various classes of extracellular peptidases that were associated with signal peptidases, relative to all genes for extracellular peptidases at that depth. SRZ, SMTZ, and MRZ, sulfate reduction zone (8 to 12 cmbsf), sulfate-methane transition zone (24 to 32 cmbsf), and methane-rich zone (24 to 28 cmbsf), respectively. (b) Relative abundances of phyla in bins at each depth. Only the 10 most abundant phyla at each depth are shown. The orange SMTZ points represent the average of two SMTZ samples, taken ∼500 m from each other, and error bars represent the ranges of the two sites.