TY - JOUR
T1 - Insights into microbial involvement in desert varnish formation retrieved from metagenomic analysis
AU - Lang-Yona, Naama
AU - Maier, Stefanie
AU - Macholdt, Dorothea S.
AU - Müller-Germann, Isabell
AU - Yordanova, Petya
AU - Rodriguez-Caballero, Emilio
AU - Jochum, Klaus P.
AU - Al-Amri, Abdullah
AU - Andreae, Meinrat O.
AU - Fröhlich-Nowoisky, Janine
AU - Weber, Bettina
AU - Mueller-Germann, Isabell
N1 - Publisher Copyright: © 2018 Society for Applied Microbiology and John Wiley & Sons Ltd
PY - 2018/6
Y1 - 2018/6
N2 - Desert varnishes are dark rock coatings observed in arid environments and might resemble Mn-rich coatings found on Martian rocks. Their formation mechanism is not fully understood and the possible microbial involvement is under debate. In this study, we applied DNA metagenomic Shotgun sequencing of varnish and surrounding soil to evaluate the composition of the microbial community and its potential metabolic function. We found that the α diversity was lower in varnish compared to soil samples (p value < 0.05), suggesting distinct populations with significantly higher abundance of Actinobacteria, Proteobacteria and Cyanobacteria within the varnish. Additionally, we observed increased levels of transition metal metabolic processes in varnish compared to soil samples. Nevertheless, potentially relevant enzymes for varnish formation were detected at low to insignificant levels in both niches, indicating no current direct microbial involvement in Mn oxidation. This finding is supported by quantitative genomic analysis, elemental analysis, fluorescence imaging and scanning transmission X-ray microscopy. We thus conclude that the distinct microbial communities detected in desert varnish originate from settled Aeolian microbes, which colonized this nutrient-enriched niche, and discuss possible indirect contributions of microorganisms to the formation of desert varnish.
AB - Desert varnishes are dark rock coatings observed in arid environments and might resemble Mn-rich coatings found on Martian rocks. Their formation mechanism is not fully understood and the possible microbial involvement is under debate. In this study, we applied DNA metagenomic Shotgun sequencing of varnish and surrounding soil to evaluate the composition of the microbial community and its potential metabolic function. We found that the α diversity was lower in varnish compared to soil samples (p value < 0.05), suggesting distinct populations with significantly higher abundance of Actinobacteria, Proteobacteria and Cyanobacteria within the varnish. Additionally, we observed increased levels of transition metal metabolic processes in varnish compared to soil samples. Nevertheless, potentially relevant enzymes for varnish formation were detected at low to insignificant levels in both niches, indicating no current direct microbial involvement in Mn oxidation. This finding is supported by quantitative genomic analysis, elemental analysis, fluorescence imaging and scanning transmission X-ray microscopy. We thus conclude that the distinct microbial communities detected in desert varnish originate from settled Aeolian microbes, which colonized this nutrient-enriched niche, and discuss possible indirect contributions of microorganisms to the formation of desert varnish.
UR - http://www.scopus.com/inward/record.url?scp=85044406599&partnerID=8YFLogxK
U2 - https://doi.org/10.1111/1758-2229.12634
DO - https://doi.org/10.1111/1758-2229.12634
M3 - مقالة
C2 - 29488349
SN - 1758-2229
VL - 10
SP - 264
EP - 271
JO - Environmental Microbiology Reports
JF - Environmental Microbiology Reports
IS - 3
ER -