Coring systems used:
EQP-01: Multi Corer, Piston Corer (long core)
EQP-02: Multi Corer, Gravity Corer
EQP-03: Gravity Corer
EQP-03a: Multi Corer, Gravity Corer (used long core system as a gravity corer)
EQP-04: Multi Corer, Gravity Corer (used long core system as a gravity corer), Piston Corer (long core)
EQP-05: Multi Corer, Gravity Corer, Piston Corer (long core)
EQP-06: Multi Corer, Gravity Corer, Piston Corer (long core)
EQP-06a: Gravity Corer
EQP-07: Multi Corer, Gravity Corer, Piston Corer (long core)
EQP-08: Multi Corer, Gravity Corer, Piston Corer (long core)
EQP-09: Gravity Corer
EQP-10: Multi Corer, Gravity Corer, Piston Corer (long core)
EQP-11: Multi Corer, Gravity Corer, Piston Corer (long core)
Excerpt from Kallmeyer et al. (2012) Supplemental Information:
For each cell enumeration, we took 2-cm3 samples from the center of a freshly cut core end using a sterile cutoff 3-cm3 syringe. We carried out cell counts according to the method of Kallmeyer et al. (2008). We extruded the 2-cm3 sediment plug into a sterile 15-mL centrifuge tube containing 8 mL of 2.5% (wt/vol) NaCl solution with 2% (vol/vol) formalin as a fixative and then thoroughly shook the tube to form a homogenous suspension. In cases where cell densities were high enough (> 105 cells/cm−3), we made direct cell counts by staining this slurry with SYBR Green I, placing a small aliquot of the slurry directly on a 0.2-μm pore size filter and enumerating manually under a fluorescence microscope (Noble and Fuhrman, 1998). Counts obtained with SYBR Green I have been found to be indistinguishable from acridine orange direct counts (AODCs) (Morono et al., 2009).
References:
Kallmeyer, J., Smith, D.C., D’Hondt, S.L., & Spivack, A.J. 2008. New cell extraction procedure applied to deep subsurface sediments. Limnol Oceanogr Methods 6:236–245. doi:10.4319/lom.2008.6.236
Kallmeyer, J., Pockalny, R., Adhikari, R. R., Smith, D. C., & D’Hondt, S. 2012. Global distribution of microbial abundance and biomass in subseafloor sediment. Proceedings of the National Academy of Sciences, 109(40), 16213-16216. doi:10.1073/pnas.1203849109
Noble, R.T., Fuhrman, J.A. 1998. Use of SYBR Green I for rapid epifluorescence counts of marine viruses and bacteria. Aquat Microb Ecol 14(2):113–118. doi:10.3354/ame014113
Morono, Y., Terada, T., Masui, N., & Inagak,i F. 2009. Discriminative detection and enumeration of microbial life in marine subsurface sediments. ISME J 3:503–511. doi:10.1038/ismej.2009.1