Dataset: Trench CFUs
Deployment: TN309

This data set is associated with PI Douglas Bartlett (NSF OCE-1536776) and R/V Thomas G. Thompson from Apr. 10 - May 20 to the Kermadec Trench adjacent to New Zealand and Schmidt Ocean Institute R/V Falkor cruise FK141109 from Nov. 9 - Dec. 9, 2014, and FK141215 from Dec. 15-21, 2014 to the Mariana Trench. During the cruises, sediment and water samples were collected. Additional details can be found at: https://schmidtocean.org/cruise/expanding-mariana-trench-perspectives/ and https://scripps.ucsd.edu/labs/dbartlett/contact/challenger-deep-cruise-2014/

Seawater (40-120 L per sample) was serially filtered through 3.0 (47 mm diameter), 0.2 (47 mm or Sterivex), and 0.1 µm (142 mm) polycarbonate filters using a peristaltic pump. Filters were then placed into a sucrose buffer (Rusch et al., 2007) and frozen at -80°C. DNA was extracted from whole filters using a protocol previously described (Fuhrman et al., 1988; Tarn et al., 2016). Negative controls using blank filters were extracted in concomitance with every extraction performed.

Microbes were cultured at 4°C on agar plates at 0.1 MPa or in transfer bulbs (Samco, Thermo Fisher Scientific) at either 0.1 MPa or high pressure. Enrichments from the Kermadec Trench were conducted using 2216 Marine Medium (2216; BD DifcoTM), A1 Medium, or a seawater minimal medium, while those from the Mariana Trench were conducted in 2216 only. For incubations at high pressure the media was inoculated, mixed with gelatin at a final concentration of 4%, transferred into bulbs, and incubated at the desired pressure (Yayanos, 2001). Kermadec Trench samples were incubated at 100 MPa while those from the Mariana Trench were incubated at in situ pressure (40-110 MPa). After ~2 months colony forming units (CFUs) were calculated and representative isolates identified via PCR using the primers 27F and 1492R.