Table 1.

Quantification of archaeal rDNA in DNA samples obtained from various naturally occurring microbial communities

SampleTemp (°C)pHDepthAmt used for extractionCell densityaDNA yieldbConcn of prokaryotic universal rDNAConcn of archaeal rDNAProportion of archaeal rDNA (%)cReference
Water and sediments from GHS855.0800 g (wet wt)106 cells/g (wet wt)3.8 ng/g (wet wt)69.4 ± 10.0 fg/g (wet wt)73.4 ± 10.3 fg/g (wet wt)106 ± 35Takai et al.d
Water and sediments from FHS854.1900 g (wet wt)106 cells/g (wet wt)3.9 ng/g (wet wt)44.8 ± 0.7 fg/g (wet wt)43.8 ± 0.8 fg/g (wet wt)97.8 ± 3.3Takai et al.d
Vent water from IVW∼300972 m12 liters107cells/liter12.5 ng/liter12.5 ± 3.5 fg/liter4.2 ± 0.7 fg/liter33.6 ± 15.8 38
Sediments from TC15–2015 cm5 g (wet wt)109 cells/g (wet wt)6.5 μg/g (wet wt)4,460 ± 840 fg/g (wet wt)42.0 ± 6.0 fg/g (wet wt)0.94 ± 0.18This study
Sediments from NE15–2015 cm5 g (wet wt)109 cells/g (wet wt)3.5 μg/g (wet wt)1,160 ± 140 fg/g (wet wt)152 ± 24 fg/g (wet wt)13.1 ± 4.2This study
  • a Direct cell count as determined with DAPI.

  • b DNA concentrations were measured with a spectrophotometer.

  • c Proportion of archaeal rDNA in whole prokaryotic universal rDNA.

  • d Takai et al., Shinkai Symp. 1998.