In the presented study, the cells of the glacial alga Ancylonema alaskanum collected in the Austrian Alps were analyzed. Algae were imaged both in their natural environment and in laboratory conditions using transmitted light and fluorescence microscopy. Using appropriate fluorochromes, the cell wall and cell organelles were studied. Oval nuclei located in the middle of the cell next to the chloroplasts and active mitochondria as well as lipid thylakoids of chloroplasts were imaged. Scanning electron microscopy showed that the surface of the algal cell wall was not significantly differentiated, and atomic force microscope imaging recorded little roughness. The SEM EDS analysis revealed that carbon, nitrogen, oxygen, and magnesium were the main components of the cells. It is worth emphasizing that the analyzed living algal cells were obtained directly from the glacier surface and demonstrated normal respiratory processes i.e. undisturbed physiological functions. Additionally, the mineral material accompanying the cells in their natural environment - fragments of the rock were imaged by Differential Interference Contrast microscopy and analyzed by Fourier Transform Infrared Spectroscopy. The study provides new data on the morphology and physicochemical characteristics of A. alaskanum, contributing to a more comprehensive characterization of their place in this harsh ecosystem.

Analytical Laboratory Institute of Chemistry Maria Curie Skłodowska University Lublin Poland

Chair and Department of Medical Microbiology Medical University of Lublin Lublin Poland

Department of Ecology Faculty of Science Charles University Prague Czech Republic

Department of Functional Anatomy and Cytobiology Institute of Biological Sciences Faculty of Biology and Biotechnology Maria Curie Skłodowska University Lublin Poland

Department of Immunobiology Institute of Biological Sciences Faculty of Biology and Biotechnology Maria Curie Skłodowska University Lublin Poland

Department of Rheumatology and Connective Tissue Diseases Medical University of Lublin Lublin Poland

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