TY - JOUR
T1 - Ancient bacteria show evidence of DNA repair.
AU - Johnson, Sarah Stewart
AU - Hebsgaard, Martin B
AU - Christensen, Torben R
AU - Mastepanov, Mikhail
AU - Nielsen, Rasmus
AU - Munch, Kasper
AU - Brand, Tina
AU - Gilbert, Tom
AU - Zuber, Maria T
AU - Bunce, Michael
AU - Rønn, Regin
AU - Gilichinsky, David
AU - Froese, Duane
AU - Willerslev, Eske
N1 - Keywords: Bacteria; Base Sequence; DNA Repair; DNA, Bacterial; Gene Amplification; Molecular Sequence Data; Soil Microbiology
PY - 2007
Y1 - 2007
N2 - Recent claims of cultivable ancient bacteria within sealed environments highlight our limited understanding of the mechanisms behind long-term cell survival. It remains unclear how dormancy, a favored explanation for extended cellular persistence, can cope with spontaneous genomic decay over geological timescales. There has been no direct evidence in ancient microbes for the most likely mechanism, active DNA repair, or for the metabolic activity necessary to sustain it. In this paper, we couple PCR and enzymatic treatment of DNA with direct respiration measurements to investigate long-term survival of bacteria sealed in frozen conditions for up to one million years. Our results show evidence of bacterial survival in samples up to half a million years in age, making this the oldest independently authenticated DNA to date obtained from viable cells. Additionally, we find strong evidence that this long-term survival is closely tied to cellular metabolic activity and DNA repair that over time proves to be superior to dormancy as a mechanism in sustaining bacteria viability.
AB - Recent claims of cultivable ancient bacteria within sealed environments highlight our limited understanding of the mechanisms behind long-term cell survival. It remains unclear how dormancy, a favored explanation for extended cellular persistence, can cope with spontaneous genomic decay over geological timescales. There has been no direct evidence in ancient microbes for the most likely mechanism, active DNA repair, or for the metabolic activity necessary to sustain it. In this paper, we couple PCR and enzymatic treatment of DNA with direct respiration measurements to investigate long-term survival of bacteria sealed in frozen conditions for up to one million years. Our results show evidence of bacterial survival in samples up to half a million years in age, making this the oldest independently authenticated DNA to date obtained from viable cells. Additionally, we find strong evidence that this long-term survival is closely tied to cellular metabolic activity and DNA repair that over time proves to be superior to dormancy as a mechanism in sustaining bacteria viability.
U2 - 10.1073/pnas.0706787104
DO - 10.1073/pnas.0706787104
M3 - Journal article
C2 - 17728401
SN - 0027-8424
VL - 104
SP - 14401
EP - 14405
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 36
ER -