Mars-like soils in the Atacama Desert, Chile, and the dry limit of microbial life.
The Viking missions showed the martian soil to be lifeless and depleted in organic material and indicated the presence of one or more reactive oxidants. Here we report the presence of Mars-like soils in the extreme arid region of the Atacama Desert. Samples from this region had organic species only at trace levels and extremely low levels of culturable bacteria. Two samples from the extreme arid region were tested for DNA and none was recovered. Incubation experiments, patterned after the Viking labeled-release experiment but with separate biological and nonbiological isomers, show active decomposition of organic species in these soils by nonbiological processes.
Navarro-González
Rafael
R
Laboratorio de Química de Plasmas y Estudios Planetarios, Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Apartado Postal 70-543, Mexico City, 04510, Mexico.
Rainey
Fred A
FA
Molina
Paola
P
Bagaley
Danielle R
DR
Hollen
Becky J
BJ
de la Rosa
José
J
Small
Alanna M
AM
Quinn
Richard C
RC
Grunthaner
Frank J
FJ
Cáceres
Luis
L
Gomez-Silva
Benito
B
McKay
Christopher P
CP
D000391:Air Microbiology; D000409:Alanine / Q000737:chemistry / Q000378:metabolism; D001419:Bacteria / Q000145:classification / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D001554:Benzene / Q000032:analysis; D044822:Biodiversity; D002677:Chile; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D003889:Desert Climate; D005561:Formates / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D020459:Genes, rRNA; D005947:Glucose / Q000737:chemistry / Q000378:metabolism; D018535:Mars; D009930:Organic Chemicals / Q000032:analysis; D010084:Oxidation-Reduction; D010777:Photochemistry; D016133:Polymerase Chain Reaction; D012988:Soil Microbiology; D013237:Stereoisomerism; D013696:Temperature
D004269:DNA, Bacterial; D005561:Formates; D009930:Organic Chemicals; C030544:formic acid; D005947:Glucose; D001554:Benzene; D000409:Alanine