Open AccessCharacterization of growing bacterial populations in M c M urdo D ry V alley soils through stable isotope probing with 18 O ‐water
Author(s) -
Schwartz Egbert,
Van Horn David J.,
Buelow Heather N.,
Okie Jordan G.,
Gooseff Michael N.,
Barrett John E.,
TakacsVesbach Cristina D.
Publication year - 2014
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/1574-6941.12349
Subject(s) - biology , soil water , stable isotope ratio , stable isotope probing , isotope , ecology , bacteria , botany , environmental chemistry , microorganism , paleontology , chemistry , physics , quantum mechanics
Soil microbial communities of the M c M urdo D ry V alleys, A ntarctica ( MDV ) contain representatives from at least fourteen bacterial phyla. However, given low rates of microbial activity, it is unclear whether this richness represents functioning rather than dormant members of the community. We used stable isotope probing ( SIP ) with 18 O ‐water to determine if microbial populations grow in MDV soils. Changes in the microbial community were characterized in soils amended with H 2 18 O and H 2 18 O ‐organic matter. Sequencing the 16 S r RNA genes of the heavy and light fractions of the bacterial community DNA shows that DNA of microbial populations was labeled with 18 O ‐water, indicating these micro‐organisms grew in the MDV soils. Significant differences existed in the community composition of the heavy and light fractions of the H 2 18 O and H 2 18 O ‐organic matter amended samples ( A nosim P < 0.05 of weighted U nifrac distance). Control samples and the light DNA fraction of the H 2 18 O amended samples were dominated by representatives of the phyla D einococcus‐ T hermus, P roteobacteria, P lanctomyces, G emmatimonadetes, A ctinobacteria and A cidobacteria, whereas P roteobacteria were more prevalent in the heavy DNA fractions from the H 2 18 O ‐water and the H 2 18 O ‐water‐organic matter treatments. Our results indicate that SIP with H 2 18 O can be used to distinguish active bacterial populations even in this low organic matter environment.