Diversity and structure of soil bacterial communities in the Fildes Region (maritime Antarctica) as revealed by 454 pyrosequencing

Abstract

This study assessed the diversity and composition of bacterial communities in four different soils (human-, penguin-, seal-colony impacted soils and pristine soil) in the Fildes Region (King George Island, Antarctica) using 454 pyrosequencing with bacterial-specific primers targeting the 16S rRNA gene. Proteobacteria, Actinobacteria, Acidobacteria, and Verrucomicrobia were abundant phyla in almost all the soil samples. The four types of soils were significantly different in geochemical properties and bacterial community structure. Thermotogae, Cyanobacteria, Fibrobacteres, Deinococcus-Thermus, and Chlorobi obviously varied in their abundance among the 4 soil types. Considering all the samples together, members of the genera Gaiella, Chloracidobacterium, Nitrospira, Polaromonas, Gemmatimonas, Sphingomonas, and Chthoniobacter were found to predominate, whereas members of the genera Chamaesiphon, Herbaspirillum, Hirschia, Nevskia, Nitrosococcus, Rhodococcus, Rhodomicrobium, and Xanthomonas varied obviously in their abundance among the four soil types. Distance-based redundancy analysis revealed that pH (p < 0.01), phosphate phosphorus (p < 0.01), organic carbon (p < 0.05), and organic nitrogen (p < 0.05) were the most significant factors that correlated with the community distribution of soil bacteria. To our knowledge, this is the first study to explore the soil bacterial communities in human-, penguin-, and seal- colony impacted soils from ice-free areas in maritime Antarctica using high-throughput pyrosequencing.

Insight into heavy metal resistome of soil psychrotolerant bacteria originating from King George Island (Antarctica)

“…We compared the taxonomic profiles obtained for each soil sample with the results of metagenomic analyses performed by other studies of soils from Antarctica. In the study by Wang et al (2015), metagenomic analysis of human-, penguin-, and seal-impacted soils as well as pristine soil from the Fildes Region (Antarctica) was performed. Considering all the samples together, members of the genera Gaiella, Chloracidobacterium, Nitrospira, Polaromonas, Gemmatimonas, Sphingomonas, and Chthoniobacter were found to predominate (Wang et al 2015).…”

“…In the study by Wang et al (2015), metagenomic analysis of human-, penguin-, and seal-impacted soils as well as pristine soil from the Fildes Region (Antarctica) was performed. Considering all the samples together, members of the genera Gaiella, Chloracidobacterium, Nitrospira, Polaromonas, Gemmatimonas, Sphingomonas, and Chthoniobacter were found to predominate (Wang et al 2015). For comparison purposes, in our study, dominants were bacteria belonging to the genera Arthrobacter, Pseudomonas, and Psychrobacter, while the genera mentioned by Wang and colleagues were represented only by seven isolates of Polaromonas from the Jardine Peak and two strains of Sphinogomonas originating from the Arctowski station.…”

Microbial Diversity of Browning Peninsula, Eastern Antarctica Revealed Using Molecular and Cultivation Methods

“…Previously, the dominance of Proteobacteria was linked with areas rich in higher organic matter (Bell et al, 2013) and moisture content (Horn et al, 2014; Niederberger et al, 2015), while dominance of Actinobacteria has been documented in arid soils (Niederberger et al, 2015), and linked to low moisture and nutrients (Takebayashi et al, 2007). Further biotic and abiotic factors, such as plants, penguins, birds, seal carcasses, and human activity are also reported to affect microbial community distributions across Antarctica (Cowan et al, 2014; Wang et al, 2015). …”

Using Ecology, Physiology, and Genomics to Understand Host Specificity inXanthomonas

“…that were virulent on pepper (13). Soil and permafrost were also mentioned as contaminated by xanthomonads (62,119,141). But the frequency and the biological relevance of such associations or contaminations are not yet known.…”