TY - JOUR
T1 - Natural abundance δ15N and δ13C of DNA extracted from soil
AU - Schwartz, Egbert
AU - Blazewicz, Steven
AU - Doucett, Richard
AU - Hungate, Bruce A.
AU - Hart, Stephen C.
AU - Dijkstra, Paul
N1 - Funding Information:
This work was supported by the Office of Science (BER), US Department of Energy (Grant no. DE-FG02-04ER63883), the National Science Foundation (Grant no. DEB-0416223) and National Research Initiative of the USDA Cooperative State Research, Education and Extension Service (Grant no. 2005-35107-16191).
PY - 2007/12
Y1 - 2007/12
N2 - We report the first simultaneous measurements of δ15N and δ13C of DNA extracted from surface soils. The isotopic composition of DNA differed significantly among nine different soils. The δ13C and δ15N of DNA was correlated with δ13C and δ15N of soil, respectively, suggesting that the isotopic composition of DNA is strongly influenced by the isotopic composition of soil organic matter. However, in all samples DNA was enriched in 13C relative to soil, indicating microorganisms fractionated C during assimilation or preferentially used 13C enriched substrates. Enrichment of DNA in 15N relative to soil was not consistently observed, but there were significant differences between δ15N of DNA and δ15N of soil for three different sites, suggesting microorganisms are fractionating N or preferentially using N substrates at different rates across these contrasting ecosystems. There was a strong linear correlation between δ15N of DNA and δ15N of the microbial biomass, which indicated DNA was depleted in 15N relative to the microbial biomass by approximately 3.4‰. Our results show that accurate and precise isotopic measurements of C and N in DNA extracted from the soil are feasible, and that these analyses may provide powerful tools for elucidating C and N cycling processes through soil microorganisms.
AB - We report the first simultaneous measurements of δ15N and δ13C of DNA extracted from surface soils. The isotopic composition of DNA differed significantly among nine different soils. The δ13C and δ15N of DNA was correlated with δ13C and δ15N of soil, respectively, suggesting that the isotopic composition of DNA is strongly influenced by the isotopic composition of soil organic matter. However, in all samples DNA was enriched in 13C relative to soil, indicating microorganisms fractionated C during assimilation or preferentially used 13C enriched substrates. Enrichment of DNA in 15N relative to soil was not consistently observed, but there were significant differences between δ15N of DNA and δ15N of soil for three different sites, suggesting microorganisms are fractionating N or preferentially using N substrates at different rates across these contrasting ecosystems. There was a strong linear correlation between δ15N of DNA and δ15N of the microbial biomass, which indicated DNA was depleted in 15N relative to the microbial biomass by approximately 3.4‰. Our results show that accurate and precise isotopic measurements of C and N in DNA extracted from the soil are feasible, and that these analyses may provide powerful tools for elucidating C and N cycling processes through soil microorganisms.
KW - DNA
KW - Natural abundance δC
KW - Natural abundance δN
KW - Soil microbial biomass
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U2 - 10.1016/j.soilbio.2007.07.004
DO - 10.1016/j.soilbio.2007.07.004
M3 - Article
AN - SCOPUS:34548555824
SN - 0038-0717
VL - 39
SP - 3101
EP - 3107
JO - Soil Biology and Biochemistry
JF - Soil Biology and Biochemistry
IS - 12
ER -