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Glacier ice and firn cores have ecological and biotechnological importance. The present study is aimed at characterizing bacteria in crustal ice cores from Svalbard, the Arctic. Counts of viable isolates ranged from 10 to 7000 CFU/ml (mean 803 CFU/ml) while the total bacterial numbers ranged from 7.20 × 104 to 2.59 × 107 cells ml−1 (mean 3.12 × 106 cells ml−1). Based on 16S rDNA sequence data, the identified species belonged to seven species, namely Bacillus barbaricus, Pseudomonas orientalis, Pseudomonas oryzihabitans, Pseudomonas fluorescens, Pseudomonas syncyanea, Sphingomonas dokdonensis, and Sphingomonas phyllosphaerae, with a sequence similarity ranging between 93.5 and 99.9% with taxa present in the database. The isolates exhibited unique phenotypic properties, and three isolates (MLB-2, MLB-5, and MLB-9) are novel species, yet to be described. To the best of our knowledge, this is the first report on characterization of cultured bacterial communities from Svalbard ice cores. We conclude that high lipase, protease, cellulase, amylase, and urease activities expressed by most of the isolates provide a clue to the potential industrial applications of these organisms. These microbes, producing cold-adapted enzymes may provide an opportunity for biotechnological research. [ABSTRACT FROM AUTHOR]

Abstract: A psychrophilic yeast species was isolated from glacier cryoconite holes of Svalbard. Nucleotide sequences of the strains were studied using D1/D2 domain, ITS region and partial sequences of mitochondrial cytochrome b gene. The strains belonged to a clade of psychrophilic yeasts, but showed marked differences from related species in the D1/D2 domain and biochemical characters. Effects of temperature, salt and media on growth of the cultures were also studied. Screening of the cultures for amylase, cellulase, protease, lipase, urease and catalase activities was carried out. The strains expressed high amylase and lipase activities. Freeze tolerance ability of the isolates indicated the formation of unique hexagonal ice crystal structures due to presence of ‘antifreeze proteins’ (AFPs). FAME analysis of cultures showed a unique trend of increase in unsaturated fatty acids with decrease in temperature. The major fatty acids recorded were oleic acid, linoleic acid, linolenic acid, palmitic acid, stearic acid, myristic acid and pentadecanoic acid. Based on sequence data and, physiological and morphological properties of the strains, we propose a novel species, Rhodotorula svalbardensis and designate strains MLB-I (CCP-II) and CRY-YB-1 (CBS 12863, JCM 19699, JCM 19700, MTCC 10952) as its type strains (Etymology: sval.bar.den′sis. N.L. fem. adj. svalbardensis pertaining to Svalbard). [Copyright &y& Elsevier]

Lichens and cryoconite (rounded or granular, brownish-black debris occurring in holes on the glacier surface) from Ny-Ålesund were used for understanding the elemental deposition pattern in the area. Lichen samples collected from low-lying coastal region and cryoconite samples from high altitudinal glacier area were processed and analysed for elements such as aluminium (Al), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), cesium (Cs), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), vanadium (V) and zinc (Zn) through inductively coupled plasma mass spectrometry. Results showed that heavy metals, Al and Fe, are present in high concentration in the cryoconite samples. Al was also present in high amounts in seven of the eight lichen samples studied. The general scheme of elements in the decreasing order of their concentrations for most of the cryoconite samples was Al > Fe > Mn > Zn > V > Pb > Cr > Ni > Cu > Co > As > Cs > Cd while that for the lichen samples was Al > Fe > Zn > Mn > Pb > Cu > Cs > Cr > Ni > V > Co > As > Cd. Similarity in trends in the two sample types confirms that the environment indeed contains these elements in that order of concentration which overtime got accumulated in the samples. Overall comparison showed most elements to be present in high concentrations in the cryoconite samples as compared to the lichen samples. Within the lichens, elemental accumulation data suggests that the low-lying site (L-2) from where Cladonia mediterranea sample was collected was the most polluted accumulating a number of elements at high concentrations. The probable reasons for such deposition patterns in the region could be natural (crustal contribution and sea salt spray) and anthropogenic (local and long-distance transmission of dust particles). In the future, this data can form a baseline for monitoring quantum of atmospheric heavy metal deposition in lichens and cryoconite of Svalbard, Arctic. [ABSTRACT FROM AUTHOR]

Abstract: This paper discusses temporal variability in the biogeochemical properties of the deeper permafrost soils of Western Spitsbergen, Arctic, that dates back up to the Middle Weichselian period (44.8ka BP). Results indicate that during the mid of the last interstadial (∼37ka BP) the chemical and biological properties of the soils were different from the stadial period that followed. Trace element concentration during the period remained low. Electrical conductivity along with K, Mg, Na, SO4 −2, Cl− and HCO3 − content of the soils during this period was high. Mineralizable nitrogen, organic carbon, biomass nitrogen and total bacterial counts were also high. These observations concurrently lead to a conclusion that the soils of Western Spitsbergen during the interstadial period were under marine influence. The culturability of bacterial cells was low which increased later with the onset of the stadial. [Copyright &y& Elsevier]

Fungal community associated with terrestrial Arctic moss, Tetraplodon mimoides was studied by examining fresh thallus tissue and adhered soil. The study resulted in the isolation of 46 microfungi belonging to 20 species in 12 genera. These included seven non-sporulating morphotypes. To the best of our knowledge, species such as Botrytis verrucosa, Mortierella simplex, M. schmuckeri, Penicillium frequentans, P. rugulosum and Cladosporium chlorocephalum are new records to the study region. All isolates were tested for production of cold-adapted amylase, pectinase, cellulase, esterase, protease, phosphatase and urease. The cultures showed varying degrees of enzyme production, with two cultures producing all seven enzymes. The present study helps in understanding the fungal diversity associated with plants growing in extreme habitats. [ABSTRACT FROM AUTHOR]

Abstract: Ten strains of cryophilic yeast were studied from glacier ice cores of Svalbard, Arctic. The ice melt samples contained about 3×103 – 1×104 colony forming unit (CFUs) per ml. Sequence analysis of the isolates, using D1/D2 domain identified five species of yeasts: Cryptococcus adeliensis (MLB-18 JX192655), Cryptococcus albidosimilis (MLB-19 JX192656), Cryptococcus saitoi (MLB-22 JX192659), Rhodosporidium lusitaniae (MLB-20 JX192657), and Rhodotorula mucilaginosa (MLB-27 JX192664). Effect of temperature on growth of these isolates was studied. The strains are able to grow at temperatures ranging between 1 and 20°C. Screening of the cultures for amylase, cellulase, protease, lipase, urease and catalase activity were carried out indicating varying amounts of enzyme production at different temperatures. Characterization of lipase in strain Cryptococcus sp. MLB-24 was performed. Fatty acid methyl ester (FAME) analysis of the cultures grown at four different temperatures (1, 4, 15, and 20°C) was also done. Decrease in temperature was reported to cause increase in concentration of unsaturated fatty acids. High amount of oleic acid accumulated with increase in temperature. These fatty acids possibly help the strains to survive in glacial ice core cold environment. The extracellular and intracellular filtrate of the cultures showed negative antifreeze protein (AFP) activity. The observations indicate that probably the isolates in the present undertaking adapt to low temperatures, by enzyme and PUFA secretion rather than by antifreeze protein secretion. [Copyright &y& Elsevier]

Obligate psychrophilic, Cryobacterium sp. MLB-32, was isolated from cryoconite holes of high Arctic glaciers. Here, we report the first draft genome sequence of the putative novel species of the genus Cryobacterium, providing opportunities for biotechnological and agricultural exploitation of its genome features., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Cryoconite holes have biogeochemical, ecological and biotechnological importance. This communication presents results on culturable psychrophilic bacterial diversity from cryoconite holes at Midre Lovénbreen (ML), Austre Brøggerbreen (AB), and Vestre Brøggerbreen (VB) glaciers. The culturable bacterial count ranged from 2.7 × 10(3) to 8.8 × 10(4) CFUs/g while the total bacterial numbers ranged from 5.07 × 10(5) to 1.50 × 10(6) cells at the three glaciers. A total of 35 morphologically distinct bacterial isolates were isolated. Based on 16S rRNA gene sequence data, the identified species belonged to eight genera namely Pseudomonas, Polaromonas, Micrococcus, Subtercola, Agreia, Leifsonia, Cryobacterium and Flavobacterium. The isolates varied in their growth temperature, NaCl tolerance, growth pH, enzyme activities, carbon utilization and antibiotic sensitivity tests. Fatty acid profiles indicate the predominance of branched fatty acids in the isolates. To the best of our knowledge, this is the first record of culturable bacterial communities and their characterization from glacier cryoconites from High Arctic. High amylase and protease activities expressed by Micrococcus sp. MLB-41 and amylase, protease and lipase activities expressed by Cryobacterium sp. MLB-32 provide a clue to the potential applications of these organisms. These cold-adapted enzymes may provide an opportunity for the prospect of biotechnology in Arctic.

Culturable bacterial diversity of Midtre Lovenbreen glacier, an Arctic glacier, was studied using 12 sediment samples collected from different points, along a transect, from the snout of Midtre Lovenbreen glacier up to the convergence point of the melt water stream with the sea. Bacterial abundance appeared to be closer to the convergence point of the glacial melt water stream with the sea than at the snout of the glacier. A total of 117 bacterial strains were isolated from the sediment samples. Based on 16S rRNA gene sequence analyses, the isolates (n=117) could be categorised in to 32 groups, with each group representing a different taxa belonging to 4 phyla (Actinobacteria, Bacilli, Flavobacteria and Proteobacteria). Representatives of the 32 groups varied in their growth temperature range (4-37 degrees C), in their tolerance to NaCl (0.1-1M NaCl) and in the growth pH range (2-13). Only 14 of 32 representative strains exhibited amylase, lipase and (or) protease activity and only one isolate (AsdM4-6) showed all three enzyme activities at 5 and 20 degrees C respectively. More than half of the isolates were pigmented. Fatty acid profile studies indicated that short-chain fatty acids, unsaturated fatty acids, branched fatty acids, cyclic and cis fatty acids are predominant in the psychrophilic bacteria.