title: Short-term effect of elevated temperature on the abundance and diversity of bacterial and archaeal amoA genes in Antarctic Soils.
abstract: Global warming will have far-reaching effects on our ecosystem. However, its effects on Antarctic soils have been poorly explored. To assess the effects of warming on microbial abundance and community composition, we sampled Antarctic soils from the King George Island in the Antarctic Peninsula and incubated these soils at elevated temperatures of 5°C and 8°C for 14 days. The reduction in total organic carbon and increase in soil respiration were attributed to the increased proliferation of Bacteria, Fungi, and Archaea. Interestingly, bacterial ammonia monooxygenase (amoA) genes were predominant over archaeal amoA, unlike in many other environments reported previously. Phylogenetic analyses of bacterial and archaeal amoA communities via clone libraries revealed that the diversity of amoA genes in Antarctic ammonia-oxidizing prokaryotic communities were temperature-insensitive. Interestingly, our data also showed that the amoA of Antarctic ammonia-oxidizing bacteria (AOB) communities differed from previously described amoA sequences of cultured isolates and clone library sequences, suggesting the presence of novel Antarctic-specific AOB communities. Denitrification-related genes were significantly reduced under warming conditions, whereas the abundance of amoA and nifH increased. Barcoded pyrosequencing of the bacterial 16S rRNA gene revealed that Proteobacteria, Acidobacteria, and Actinobacteria were the major phyla in Antarctic soils and the effect of short-term warming on the bacterial community was not apparent.
authors.affiliation: Department of Environmental Science and Ecological Engineering, Korea University, Seoul 136-713, Republic of Korea.
authors.forename: Jiwon
authors.initials: J
authors.lastname: Han
authors.forename: Jaejoon
authors.initials: J
authors.lastname: Jung
authors.forename: Minsuk
authors.initials: M
authors.lastname: Park
authors.forename: Seunghun
authors.initials: S
authors.lastname: Hyun
authors.forename: Woojun
authors.initials: W
authors.lastname: Park
mesh_terms: D000864:Antarctic Regions; D001105:Archaea / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D019843:Archaeal Proteins / Q000235:genetics*; D001419:Bacteria / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D001426:Bacterial Proteins / Q000235:genetics*; D044822:Biodiversity; D017753:Ecosystem; D006358:Hot Temperature; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000235:genetics*; D010802:Phylogeny; D012988:Soil Microbiology
chemical_list: D019843:Archaeal Proteins; D001426:Bacterial Proteins; D010088:Oxidoreductases; C045582:ammonia monooxygenase