Sulphate Reducing Activity Detected in Soil Samples from Antarctica, Ecology Glacier Forefield, King George Island

Abstract

We determined sulphate-reducing activities in media inoculated with soils and with kettle lake sediments in order to investigate their potential in geomicrobiological processes in low-temperature, terrestrial maritime Antarctic habitats. Soil and sediment samples were collected in a glacier valley abandoned by Ecology Glacier during the last 30 years: from a new formed kettle lake sediment and forefield soil derived from ground moraine. Inoculated with these samples, liquid Postgate C and minimal media supplemented with various carbon sources as electron donors were incubated for 8 weeks at 4°C. High rates of sulphate reduction were observed only in media inoculated with soil. No sulphate reduction was detected in media inoculated with kettle lake sediments. In soil samples culture media calcite and elemental sulphur deposits were observed, demonstrating that sulphate-reducing activity is associated with a potential to mineral formation in cold environments. Cells observed on scanning microscopy (SEM) micrographs of post-culture-soil deposits could be responsible for sulphate-reducing activity.

Enrichment of Cryoconite Hole Anaerobes: Implications for the Subglacial Microbiome

“…Incubation was carried out at 4 °C for 10 weeks. Sulfide precipitation was indicated by Wolicka et al [ 34 ].…”

Caracterização da microbiota marinha sob influência do degelo glacial na Baía do Almirantado, Antártica

“…Austral e no gelo marinho (ver referências em WILKINS et al, 2013a), além de ambientes anóxicos como os lagos Antárticos (FRANZMANN et al, 1991;SATTLEY et al, 2007; crioconitos no gelo, onde estão associados à redução de sulfato (ZDANOWSKI et al, 2017). (WOLICKA et al, 2014) No geral, a Baía do Almirantado apresenta uma dinâmica temporal similar à de águas superficiais do verão antártico, com aumento de grupos associados aos blooms de fitoplâncton ao longo do verão, os quais que se aproveitam da alta disponibilização de carbono orgânico dissolvido para o seu crescimento (GHIGLIONE et al, 2012;WILLIAMS et al, 2012;LURIA et al, 2016;SIGNORI et al, 2017). Entretanto, a diversidade da comunidade microbiana não decaiu ao longo do verão, como costuma ocorrer em condições copiotróficas e de estabilização da coluna d'água (GHIGLIONE et al, 2012;LURIA et al, 2016;SIGNORI et al, 2017;GUTIÉRREZ et al, 2018).…”