Fig 1.
Pelagic sample collection locations within the Kermadec and Mariana trenches.
Fig 2.
Microbial activity as a function of pressure using HPG.
A; Ratio of the percentage of active cells under in situ pressure versus atmospheric pressure. B; Ratio of the percentage of active cells at 110 MPa versus in situ pressure. Filled circles, seawater collected at <13°C, excluding the surface sample; open circles, seawater collected at >15°C.
Fig 3.
Relative abundances of the ten most abundant phyla in the pelagic zones of the Kermadec and Mariana trenches, organized by trench and size fraction (>3.0, 3.0–0.2, 0.2–0.1 μm).
Fig 4.
Ordinations of sequenced abyssal and hadal communities.
Distances between abyssal and hadal communities visualized via ordinations using Bray-Curtis dissimilarity. A, Mariana Trench; B, Kermadec Trench; C, both trenches.
Fig 5.
OTUs enriched in the hado- or abysso- pelagic communities.
A; OTUs showing enrichment within the hadal or abyssal zones of the Mariana and Kermadec trenches labeled by the lowest discernible taxonomic rank. Filled, enriched in the abyssal zone; open, enriched in the hadal zone. B; OTUs showing enrichment within the hadal zone of the Kermadec or Mariana trench. Filled, enriched in the Kermadec Trench; open, enriched in the Mariana Trench.
Fig 6.
Isolates and their abundances.
A; Relative abundances of cultured isolates from seawater in the Kermadec and Mariana trenches at 0.1 MPa and 4°C on plates (n = 170) or in bulbs (n = 31). B; Combined relative abundances of OTUs similar to piezophilic Colwellia, Shewanella, Moritella, or Psychromonas species derived from the community data. C; Combined relative abundances of OTUs related to the genera Pseudoalteromonas, Pseudomonas, Psychrobacter, Halomonas, Shewanella, and Vibrio derived from the community data.