Objectives

The increasing interest in unraveling the microorganisms’ diversity in ice environments (1) for identifying stable molecules that confer higher efficiency for various biotechnological applications at low temperatures, (2) for studying species conservation and defining climate-related biomarkers, and (3) for elaborating models for exobiology studies of ice-containing planets, extended only recently to the investigation of ice caves ecosystems.

In this context, our goal is to identify the biodiversity of microorganisms living in ice deposits from Scarisoara Cave (Romania), a very little studied environment of highly preserved psychrophilic and psychrotolerant communities, and to discover putative climate biomarkers by correlating the chronological distribution of microorganisms in ice block with the climate characteristics recorded chronologically in the corresponding ice layers. This phylogenetic and physiological study of uncultivated and cultivated microorganisms isolated from Scarisoara cave’s ice layers and ice lakes encompasses bacteria, archaea, and eukaryotic microorganisms. Cyanobacteria from this type of environment present a particular interest as cold-adapted photoautotrophs. The presence of these photosynthetic microorganisms will be investigated in ice from both actual and ancient light-exposed sites of the cave, to assess their contribution to carbon and nitrogen cycles in this habitat. Newly determined microorganisms will be further investigated in view of selecting and characterizing new cold-adapted species with applicative potential in biotechonologies.

Accordingly, the proposed project is directly related to the objectives of FP7 Environment theme, and of the National Plan for Research, Development and Innovation 2007-2013 (PNII), Life Science Domain, Evolutionary, population and environmental biology (LS8) Subdomain.

The proposed study is relevant for both (1) fundamental research, by determining the biodiversity of an practically uncharacterized type of ecosystem, and by obtaining an integrative picture of time-related and substrate geochemistry-related variations of the microorganisms community, that assess for their conservation and allows to define possible climate biomarkers, and (2) applicative research, by isolating new microorganisms adapted to low temperatures that possess stable molecules of high interest for applications in medicine and nanotechnologies.

This interdisciplinary research covers a large spectrum of disciplines: biospeleology, microbiology, molecular biology, geochemistry, bioinstrumentation, and bioinformatics.

The principal objectives of the project are 1) to study the microbial diversity in ice samples collected from Scarisoara Cave from phylogenetic and physiological perspective, using culture-dependent and culture-independent approaches, 2) to analyze the diversity and chronological distribution of microbial communities in ice sediments in correlation with light exposure, geochemical composition and corresponding climate patterns to identify climate biomarker, and 3) to isolate new psychrophilic / psychrotolerant strains of putative biotechnological interest.

The novelty and originality of this study consist of 1) the identification of an ice cave microbiota representing an almost undocumented type of ecosystem, 2) adding the biological element to a thorough geological and paleoclimate description of Scarisoara Cave for obtaining an integrative characterization of such ice environment, 3) establishing a relationship between the microbial biodiversity chronosequence from cave ice sediments and the climate embedded information, and 4) providing new opportunities for identifying cold-adapted species that extends the offer of advanced molecules in biotechnologies.