Enrichment of cryoconite hole anaerobes: implications for the subglacial microbiome

Glaciers have recently been recognized as ecosystems, comprised of several distinct habitats: a sunlit and oxygenated glacial surface, glacial ice and a dark, mostly anoxic glacial bed. Surface meltwaters annually flood the subglacial sediments by means of drainage channels. Glacial surfaces host aquatic microhabitats called cryoconite holes, regarded as “hot spots” of microbial abundance and activity, largely contributing to the meltwaters’ bacterial diversity. This study presents an investigation of cryoconite hole anaerobes and discusses their possible impact on subglacial microbial communities, combining 16S rRNA gene fragment amplicon sequencing and the traditional enrichment culture technique. Cryoconite hole sediment harbored bacteria belonging mainly to the Proteobacteria (21%), Bacteroidetes (16%), Actinobacteria (14%) and Planctomycetes (6%) phyla. An 8 week incubation of those sediments in Postgate C medium for sulfate reducers in air tight bottles, emulating subglacial conditions, eliminated a great majority of dominant taxa, leading to enrichment of the Firmicutes (62%), Proteobacteria (14%) and Bacteroidetes (13%), which consisted of anaerobic genera like Clostridium, Psychrosinus, Paludibacter and Acetobacterium. Enrichment of Pseudomonas spp. also occurred, suggesting it played a role as a dominant oxygen scavenger, providing a possible scenario for anaerobic niche establishment in subglacial habitats. To our knowledge this is the first paper to provide insight into the diversity of the anaerobic part of the cryoconite hole microbial community and its potential to contribute to matter turnover in anoxic, subglacial sites

A smelly business: microbiology of Adélie penguin guano (Point Thomas rookery, Antarctica)

Adélie penguins (Pygoscelis adeliae) are the most numerous flightless bird group breeding in coastal areas of Maritime and Continental Antarctica. Their activity leaves a mark on the land in the form of large guano deposits. This guano is an important nutrient source for terrestrial habitats of ice-free Antarctic areas, most notably by being the source of ammonia vapors which feed the surrounding grass, lichen and algae communities. Although investigated by researchers, the fate of the guano-associated microbial community and its role in decomposition processes remain vague. Therefore, by employing several direct community assessment methods combined with a broad culture-based approach we provide data on bacterial numbers, their activity and taxonomic affiliation in recently deposited and decayed Adélie penguin guano sampled at the Point Thomas rookery in Maritime Antarctica (King George Island). Our research indicates that recently deposited guano harbored mostly bacteria of penguin gut origin, presumably inactive in cold rookery settings. This material was rich in mesophilic enzymes active also at low temperatures, likely mediating early stage decomposition. Fresh guano colonization by environmental bacteria was minor, accomplished mostly by ammonia scavenging Jeotgalibaca sp. cells. Decayed guano contained 10-fold higher bacterial numbers with cold-active enzymes dominating the samples. Guano was colonized by uric-acid degrading and lipolytic Psychrobacter spp. and proteolytic Chryseobacterium sp. among others. Several spore-forming bacteria of penguin gut origin persisted in highly decomposed material, most notably uric-acid fermenting members of the Gottschalkiaceae family

Plasmids of Psychrotolerant Polaromonas spp. Isolated From Arctic and Antarctic Glaciers – Diversity and Role in Adaptation to Polar Environments

Cold-active bacteria of the genus Polaromonas (class Betaproteobacteria) are important components of glacial microbiomes. In this study, extrachromosomal replicons of 26 psychrotolerant Polaromonas strains, isolated from Arctic and Antarctic glaciers, were identified, sequenced, and characterized. The plasmidome of these strains consists of 13 replicons, ranging in size from 3,378 to 101,077 bp. In silico sequence analyses identified the conserved backbones of these plasmids, composed of genes required for plasmid replication, stable maintenance, and conjugal transfer. Host range analysis revealed that all of the identified plasmids are narrow-host-range replicons, only able to replicate in bacteria of closely related genera (Polaromonas and Variovorax) of the Comamonadaceae family. Special attention was paid to the identification of plasmid auxiliary genetic information, which may contribute to the adaptation of bacteria to environmental conditions occurring in glaciers. Detailed analysis revealed the presence of genes encoding proteins potentially involved in (i) protection against reactive oxygen species, ultraviolet radiation, and low temperatures; (ii) transport and metabolism of organic compounds; (iii) transport of metal ions; and (iv) resistance to heavy metals. Some of the plasmids also carry genes required for the molecular assembly of iron–sulfur [Fe-S] clusters. Functional analysis of the predicted heavy metal resistance determinants demonstrated that their activity varies, depending on the host strain. This study provides the first molecular insight into the mobile DNA of Polaromonas spp. inhabiting polar glaciers. It has generated valuable data on the structure and properties of a pool of plasmids and highlighted their role in the biology of psychrotolerant Polaromonas strains and their adaptation to the environmental conditions of Arctic and Antarctic glaciers

Effects of genistein on insulin pathway-related genes in mouse differentiated myoblast C2C12 cell line: evidence for two independent modes of action

Introduction. Genistein (plant isoflavone) is a well-known anti-cancer drug with estrogenic-like properties. Genistein also regulates sugar and lipid metabolism; thus, it has anti-diabetic properties. The aim of the study was to evaluate in vitro effects of genistein on glucose transport, fatty acids oxidation, activation of PKB, and expression of genes related to insulin pathway in differentiated myoblast C2C12 mouse cell line. Material and methods. Differentiated myoblast C2C12 mouse cell line was used to assess the effects of different genistein concentrations on glucose transport and fatty acids oxidation measured by radioactivity technique, activation of PKB, and expression of selected genes related to insulin signaling pathway (IR-a, IR-b, IRS-1, PKB, GLUT-4, PP2A, SH-PTP2) at the mRNA and protein levels. Cells were incubated with various concentrations of genistein under standard conditions for 0–48 hours.Results. Genistein in low concentrations (0.1–1 μM) significantly increased glucose transport and decreased fatty acids oxidation in C2C12 cells after 48 h of incubation. High concentration of genistein (50 μM) had the opposite effect. Genistein stimulated PKB phosphorylation during the first 5–10 minutes of incubation. There was no significant impact on the protein expression of selected genes (IR-a, IR-b, IRS-1, PKB, GLUT-4, PP2A-Ca, ER-a and ER-b) after 48 h treatment. We observed inverse correlation between genistein concentration and the expression of SH-PTP2 protein. Genistein affected the expression pattern of mRNAs for genes related to the insulin pathway, however, not the expression of the encoded proteins. Conclusions. The results of this study showed that depending on the concentration and time of incubation genistein significantly affects glucose and lipid metabolism and at low concentration modifies expression patternof a few genes in C2C12 cells

Evidence of adaptation, niche separation and microevolution within the genus Polaromonas on Arctic and Antarctic glacial surfaces

Polaromonas is one of the most abundant genera found on glacier surfaces, yet it’s ecology remains poorly described. Investigations made to date point towards a uniform distribution of Polaromonas phylotypes across the globe. We compared 43 Polaromonas isolates obtained from surfaces of Arctic and Antarctic glaciers to address this issue. 16S rRNA gene sequences, intergenic transcribed spacers (ITS) and metabolic fingerprinting showed great differences between hemispheres but also between neighboring glaciers. Phylogenetic distance between Arctic and Antarctic isolates indicated separate species. The Arctic group clustered similarly, when constructing dendrograms based on 16S rRNA gene and ITS sequences, as well as metabolic traits. The Antarctic strains, although almost identical considering 16S rRNA genes, diverged into 2 groups based on the ITS sequences and metabolic traits, suggesting recent niche separation. Certain phenotypic traits pointed towardscell adaptation to specific conditions on a particular glacier, like varying pH levels. Collected data suggest, that seeding of glacial surfaces with Polaromonas cells transported by various means, is of greater efficiency on local than global scales. Selection mechanisms present of glacial surfaces reduce the deposited Polaromonas diversity, causing subsequent adaptation to prevailing environmental conditions. Furthermore, interactions with other supraglacial microbiota, like algae cells may drive postselectional niche separation and microevolution within the Polaromonas genus

Security theory and practice: Stablisation and reconstrution of post-conlict areas in the 21st century

Wprowadzenie: Cieszymy się, że możemy skierować do Państwa rąk kolejny numer periodyku „Bezpieczeństwo.Teoria i Praktyka”, tym razem poświęcony problematyce stabilizacji i odbudowy obszarów pokonfliktowych w XXI w. Podjęty temat jest niezwykle ważny, ponieważ żyjemy w czasach nieuporządkowanego świata, w którym liczba konfliktów zbrojnych o różnej skali i charakterze oraz wynikające z nich konsekwencje wpływają destrukcyjnie na ład międzynarodowy.Umiędzynarodowienie konfliktów wewnętrznych pełni często funkcję instrumentalną w grze, której stawką jest zajęcie przez dane państwo właściwego – z punktu widzenia jego decydentów – miejsca w nowym systemie ról międzynarodowych. Przykładem tego jest wojna domowa w Syrii, którą Jerzy Zdanowski w artykule rozpoczynającym tom traktuje jako „wojnę zastępczą”. Krótko przedstawia także istotę rekonstrukcji obszarów pokonfliktowych, czym jako badacz rozwija myśli pułkownika Piotra Gąstała, wieloletniego żołnierza i dowódcy Jednostki Wojskowej GROM, który podczas swojej służby przebywał w niejednym państwie dotkniętym konfliktem zbrojnym i wojną oraz ich skutkami. W udzielonym wywiadzie odnosi się on do zagadnienia stabilizacji ze swojej perspektywy – praktyka, któremu nie raz, na terenie prowadzenia działań wojskowych, przyszło mierzyć się z tym wszystkim, co kryje się pod tym pojęciem. Należy przy tym uwzględnić, że jako żołnierz jednostki specjalnej wykonywał tam specyficzne działania. O tym, jak podchodzą do nich nie tylko praktycy, ale i badacze, pisze Piotr Orłowski, analizując znaczenie sił specjalnych jako narzędzia stabilizacji na obszarach pokonfliktowych

Administration of Rhodiola kirilowii Extracts during Mouse Pregnancy and Lactation Stimulates Innate but Not Adaptive Immunity of the Offspring

The use of antibiotics during pregnancy and lactation is associated with an increased risk of developmental disorders. One of the natural medicinal plants—Rhodiola kirilowii, widely used as an immunostimulant in adults—might be a good alternative to antibiotic treatment. The aim of present study was to assess whether daily oral administration of 20 mg/kg of Rhodiola kirilowii aqueous (RKW) or 50% hydroalcoholic (RKW-A) extracts affected hematological and immunological parameters of 6-week-old mouse progeny. There was no significant change in hematological parameters of blood with the exception of hemoglobin, which was significantly higher (about 4%) in RKW group. Offspring of mothers fed Rhodiola kirilowii extracts had increased percentage of granulocytes and decreased percentage of lymphocytes. These changes correlated with decreased percentage of CD3+/CD4+ T-cells (RKW and RKW-A), decrease of CD8+ cells, and increase percentage of NK cells in RKW group. In addition, both types of Rhodiola kirilowii extracts stimulated granulocyte phagocytosis and increased level of respiratory burst. In conclusion, the long-term supplementation of mouse mothers during pregnancy and lactation with RKW or RKW-A extracts affects the immune system of their progeny. These results should be taken into consideration before administration of Rhodiola kirilowii to pregnant and lactating women

Allergic cross-reactivity – anew challenge for allergists?

Allergic cross-reactivity is an important epidemiological issue in all age groups. It is caused by a non-specific binding of both primary allergen as well as allergens causing secondary cross-reactivity by the same IgE antibodies. This phenomenon results from the similarity of the molecular structure of allergen epitopes and leads to a number of allergic cross-reactivity syndromes, such as pollen-food syndromes, pork-cat syndrome or latex-fruit syndrome. They are characterized by rich symptomatology and the possible occurrence of symptoms related to various systems, including life-threatening systemic reactions. In many cases, specific allergen groups responsible for certain cross-reactions, such as plant profilins, fish parvalbumins or invertebrate tropomyosins, have been identified. Also, some of the factors affecting the spatial conformation of allergens, and thus modifying their allergenic potential, have been identified. Despite all these achievements, the diagnostics of cross reactivity syndromes still remains difficult due to the limited available methods and the possible occurrence of overlapping phenomena such as co-sensitisation, asymptomatic cross-sensitisation or IgE-independent or nonimmunological adverse drug reactions. Therefore, careful management based on medical history as well as avoidance of unjustified treatment methods, e.g. diet therapy or immunotherapy, are necessary. This is of great importance as the incidence of food allergies is expected to increase mainly due to the progressive rise in the prevalence of inhalant allergies to pollens