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1.
Curr Microbiol ; 81(5): 115, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483599

RESUMO

The diversity of bacteria associated with alpine lichens was profiled. Lichen samples belonging to the Umbilicariaceae family, commonly known as rock tripe lichens, were gathered from two distinct alpine fellfields: one situated on Mt. Brennkogel located in the Eastern European Alps (Austria), and the other on Mt. Stanley located in the Rwenzori mountains of equatorial Africa (Uganda). The primary aim of this research was to undertake a comparative investigation into the bacterial compositions, and diversities, identifying potential indicators and exploring their potential metabolisms, of these lichen samples. Bulk genomic DNA was extracted from the lichen samples, which was used to amplify the 18S rRNA gene by Sanger sequencing and the V3-V4 region of the 16S rRNA gene by Illumina Miseq sequencing. Examination of the fungal partner was carried out through the analysis of 18S rRNA gene sequences, belonging to the genus Umbilicaria (Ascomycota), and the algal partner affiliated with the lineage Trebouxia (Chlorophyta), constituted the symbiotic components. Analyzing the MiSeq datasets by using bioinformatics methods, operational taxonomic units (OTUs) were established based on a predetermined similarity threshold for the V3-V4 sequences, which were assigned to a total of 26 bacterial phyla that were found in both areas. Eight of the 26 phyla, i.e. Acidobacteriota, Actinomycota, Armatimonadota, Bacteroidota, Chloroflexota, Deinococcota, Planctomycetota, and Pseudomonadota, were consistently present in all samples, each accounting for more than 1% of the total read count. Distinct differences in bacterial composition emerged between lichen samples from Austria and Uganda, with the OTU frequency-based regional indicator phyla, Pseudomonadota and Armatimonadota, respectively. Despite the considerable geographic separation of approximately 5430 km between the two regions, the prediction of potential metabolic pathways based on OTU analysis revealed similar relative abundances. This similarity is possibly influenced by comparable alpine climatic conditions prevailing in both areas.


Assuntos
Ascomicetos , Clorófitas , Líquens , Líquens/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Filogenia , Bactérias/genética , Ascomicetos/genética , Clorófitas/genética , África
2.
Sci Total Environ ; 807(Pt 2): 150874, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34627905

RESUMO

Cryoconite is a mixture of mineral and organic material covering glacial ice, playing important roles in biogeochemical cycles and lowering the albedo of a glacier surface. Understanding the differences in structure of cryoconite across the globe can be important in recognizing past and future changes in supraglacial environments and ice-organisms-minerals interactions. Despite the worldwide distribution and over a century of studies, the basic characteristics of cryoconite, including its forms and geochemistry, remain poorly studied. The major purpose of our study is the presentation and description of morphological diversity, chemical and photoautotrophs composition, and organic matter content of cryoconite sampled from 33 polar and mountain glaciers around the globe. Observations revealed that cryoconite is represented by various morphologies including loose and granular forms. Granular cryoconite includes smooth, rounded, or irregularly shaped forms; with some having their surfaces covered by cyanobacteria filaments. The occurrence of granules increased with the organic matter content in cryoconite. Moreover, a major driver of cryoconite colouring was the concentration of organic matter and its interplay with minerals. The structure of cyanobacteria and algae communities in cryoconite differs between glaciers, but representatives of cyanobacteria families Pseudanabaenaceae and Phormidiaceae, and algae families Mesotaeniaceae and Ulotrichaceae were the most common. The most of detected cyanobacterial taxa are known to produce polymeric substances (EPS) that may cement granules. Organic matter content in cryoconite varied between glaciers, ranging from 1% to 38%. The geochemistry of all the investigated samples reflected local sediment sources, except of highly concentrated Pb and Hg in cryoconite collected from European glaciers near industrialized regions, corroborating cryoconite as element-specific collector and potential environmental indicator of anthropogenic activity. Our work supports a notion that cryoconite may be more than just simple sediment and instead exhibits complex structure with relevance for biodiversity and the functioning of glacial ecosystems.


Assuntos
Efeitos Antropogênicos , Camada de Gelo , Ecossistema , Humanos , Minerais
3.
Front Plant Sci ; 12: 689119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34290725

RESUMO

Snow algae are photosynthetic microbes that inhabit the melting snow surface in alpine and polar regions. We analyzed the pigment and species composition of colored snow collected on Mt. Tateyama in Japan during the melting seasons of 2015 and 2016. High-performance liquid chromatographic analyses of the pigments extracted from the colored snow showed that their composition varied within the study area and were classified into four types: Type A (astaxanthin-monoester dominant), Type B (medium astaxanthin-monoester content), Type C (abundant primary carotenoids and free-astaxanthin), and Type D (abundant primary carotenoids and astaxanthin diesters). Types A and B were most commonly observed in the study area, whereas Types C and D appeared only at specific sites. Analysis of the 18S ribosomal RNA (18S rRNA) gene revealed six major amplicon sequence variants (ASVs) of snow algae, belonging to the Sanguina, Chloromonas, and Chlainomonas groups. The relative abundance of the algal ASVs showed that Sanguina was dominant (>48%) in both Types A and B, suggesting that the difference in astaxanthin abundance between the two types was caused by the production of pigments in the algal cells. The algal community structures of Types C and D differed from those of Types A and B, indicating that the primary carotenoids and astaxanthin diesters were derived from certain algal species in these types. Therefore, astaxanthin-rich Sanguina algae mostly induced the red snow that appeared widely in this alpine area; however, they were partially dominated by Chloromonas or Chlainomonas algae, causing different pigment compositions.

4.
Sci Total Environ ; 788: 147623, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34023597

RESUMO

Airborne pollens cause pollinosis and have the potential to affect microphysics in clouds; however, the number of monitored species has been very limited due to technical difficulties for the morphotype identification. In this study, we applied an eDNA approach to the airborne pollen communities in the suburbs of the Tokyo metropolitan area in Japan, within a mixed urban, rural, and mountain landscape, revealing pollen seasonality of various taxa (a total of 78 families across the period) in the spring season (February to May). Those taxa distinctly shifted in the season, especially in the beginning of February and the middle of April. Air temperature shift was an obvious key factor to affect the airborne pollen community, while the influence of other meteorological factors, such as wind speed, humidity, and precipitation, was not clear. Taxonomic classification of major Amplicon Sequence Variants (ASVs) indicates multiple pollen sources, including natural forest, planted forest, roadside, park lands, and horticultural activities. Most major ASV belongs to Japanese cedar (Cryptomeria japonica), which is the most notable allergen that causes pollinosis in Japan, peaking in mid-February to March. Backward trajectory analysis of air masses suggests that the Japanese cedar and other Cupressaceae plantation forests in the western mountains were a significant source of airborne pollen communities detected at our sampling site. Other major plant pollen sources, including Japanese zelkova (Zelkova serrata) and ginkgo (Ginkgo biloba), emanated from the nearby parks or roadside regions. This study's approach enables us to visualize the phenology of multiple pollen, including timing and duration. Long-term monitoring of this type would provide additional insight into understanding the role of climate change on pollen transmission and links to flowering events.


Assuntos
Cryptomeria , Pólen , Alérgenos , Humanos , Japão , Estações do Ano , Tóquio
5.
Genes Genomics ; 42(9): 1087-1096, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32737807

RESUMO

BACKGROUND: Spingobium sp. PAMC 28499 is isolated from the glaciers of Uganda. Uganda is a unique region where hot areas and glaciers coexist, with a variety of living creatures surviving, but the survey on them is very poor. The genetic character and complete genome information of Sphingobium strains help with environmental studies and the development of better to enzyme industry. OBJECTIVE: In this study, complete genome sequence of Spingobium sp. PAMC 28499 and comparative analysis of Spingobium species strains isolated from variety of the region. METHODS: Genome sequencing was performed using PacBio sequel single-molecule real-time (SMRT) sequencing technology. The predicted gene sequences were functionally annotated and gene prediction was carried out using the program NCBI non-redundant database. And using dbCAN2 and KEGG data base were degradation pathway predicted and protein prediction about carbohydrate active enzymes (CAZymes). RESULTS: The genome sequence has 64.5% GC content, 4432 coding protein coding genes, 61 tRNAs, and 12 rRNA operons. Its genome encodes a simple set of metabolic pathways relevant to pectin and its predicted degradation protein an unusual distribution of CAZymes with extracellular esterases and pectate lyases. CAZyme annotation analyses revealed 165 genes related to carbohydrate active, and especially we have found GH1, GH2, GH3, GH38, GH35, GH51, GH51, GH53, GH106, GH146, CE12, PL1 and PL11 such as known pectin degradation genes from Sphingobium yanoikuiae. These results confirmed that this Sphingobium sp. strain PAMC 28499 have similar patterns to RG I pectin-degrading pathway. CONCLUSION: In this study, isolated and sequenced the complete genome of Spingobium sp. PAMC 28499. Also, this strain has comparative genome analysis. Through the complete genome we can predict how this strain can store and produce energy in extreme environment. It can also provide bioengineered data by finding new genes that degradation the pectin.


Assuntos
Polissacarídeo-Liases/genética , Sphingomonadaceae/genética , Sphingomonas/genética , Composição de Bases/genética , Sequência de Bases/genética , Mapeamento Cromossômico/métodos , Genoma Bacteriano/genética , Genômica/métodos , Pectinas/metabolismo , Filogenia , Sphingomonadaceae/enzimologia , Sphingomonadaceae/metabolismo , Sphingomonas/metabolismo , Uganda , Sequenciamento Completo do Genoma/métodos
6.
Proc Natl Acad Sci U S A ; 117(24): 13275-13282, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32482865

RESUMO

Microorganisms are ubiquitous and highly diverse in the atmosphere. Despite the potential impacts of airborne bacteria found in the lower atmosphere over the Southern Ocean (SO) on the ecology of Antarctica and on marine cloud phase, no previous region-wide assessment of bioaerosols over the SO has been reported. We conducted bacterial profiling of boundary layer shipboard aerosol samples obtained during an Austral summer research voyage, spanning 42.8 to 66.5°S. Contrary to findings over global subtropical regions and the Northern Hemisphere, where transport of microorganisms from continents often controls airborne communities, the great majority of the bacteria detected in our samples were marine, based on taxonomy, back trajectories, and source tracking analysis. Further, the beta diversity of airborne bacterial communities varied with latitude and temperature, but not with other meteorological variables. Limited meridional airborne transport restricts southward community dispersal, isolating Antarctica and inhibiting microorganism and nutrient deposition from lower latitudes to these same regions. A consequence and implication for this region's marine boundary layer and the clouds that overtop it is that it is truly pristine, free from continental and anthropogenic influences, with the ocean as the dominant source controlling low-level concentrations of cloud condensation nuclei and ice nucleating particles.


Assuntos
Microbiologia do Ar , Bactérias/isolamento & purificação , Oceanos e Mares , Aerossóis/análise , Regiões Antárticas , Bactérias/classificação , Bactérias/genética , Geografia , Microbiota , Água do Mar/microbiologia , Temperatura
7.
Int J Syst Evol Microbiol ; 70(6): 3711-3717, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32416741

RESUMO

Twenty-one psychrophilic yeast isolates related to the Camptobasidiaceae family in the Microbotryomycetes class were obtained from ice collected from cold environments worldwide. A new psychrophilic species from the recently described genus Cryolevonia, Cryolevania giraudoae is proposed to accommodate 18 isolates from Patagonia (Argentina) and Antarctica (holotype CRUB 2086T). In addition, a new psychrophilic species in the genus Camptobasidium is described as Camptobasidium gelus sp. nov. (holotype CBS 8941T), based on three isolates from glacial ice in the Russel glacier (Greenland ice sheet) and Antarctica. The strict psychrophilic profile is the salient feature of both novel species.


Assuntos
Basidiomycota/classificação , Camada de Gelo/microbiologia , Filogenia , Regiões Antárticas , Argentina , Basidiomycota/isolamento & purificação , DNA Fúngico/genética , Técnicas de Tipagem Micológica , Análise de Sequência de DNA
8.
Front Microbiol ; 10: 1572, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379765

RESUMO

In order to study airborne bacterial community dynamics over Tokyo, including fine-scale correlations between airborne microorganisms and meteorological conditions, and the influence of local versus long-range transport of microbes, air samples were collected on filters for periods ranging from 48 to 72 h. The diversity of the microbial community was assessed by next generation sequencing. Predicted source regions of airborne particles, from back trajectory analyses, changed abruptly from the Pacific Ocean to the Eurasian Continent in the beginning of October. However, the microbial community composition and the alpha and beta diversities were not affected by this shift in meteorological regime, suggesting that long-range transport from oceanic or continental sources was not the principal determinant controlling the local airborne microbiome. By contrast, we found a significant correlation between the local meteorology, especially relative humidity and wind speed, and both alpha diversity and beta diversity. Among four potential local source categories (soil, bay seawater, river, and pond), bay seawater and soil were identified as constant and predominant sources. Statistical analyses point toward humidity as the most influential meteorological factor, most likely because it is correlated with soil moisture and hence negatively correlated with the dispersal of particles from the land surface. In this study, we have demonstrated the benefits of fine-scale temporal analyses for understanding the sources and relationships with the meteorology of Tokyo's "aerobiome."

9.
FEMS Microbiol Ecol ; 95(7)2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31132102

RESUMO

Cryoconite granules are dark-colored biological aggregates on glaciers. Bacterial community varies with granule size, however, community change in space and their susceptibility to environmental factors has not been described yet. Therefore, we focused on bacterial community from four different granule sizes (30-249 µm, 250-750 µm, 750-1599 µm, more than 1600 µm diameter) in 10 glaciers in northwestern Greenland and their susceptibility to exogenous nutrients in cryoconite hole. A filamentous cyanobacterium Phormidesmis priestleyi, which has been frequently reported from glaciers in Arctic was abundant (10%-26%) across any size of granules on most of glaciers. Bacterial community across glaciers became similar with size increase, and whence smallest size fractions contain more unique genera in each glacier. Multivariate analysis revealed that effect of nutrients to beta diversity is larger in smaller granules (30-249 µm and 250-750 µm diameter), suggesting that bacterial susceptibility to nutrients changes with growth of granule (i.e. P. priestleyi was affected by nitrate in early growth stage).


Assuntos
Camada de Gelo/química , Camada de Gelo/microbiologia , Microbiota , Nutrientes/análise , Cianobactérias/classificação , Cianobactérias/crescimento & desenvolvimento , Cianobactérias/isolamento & purificação , Cianobactérias/metabolismo , Groenlândia , Nutrientes/metabolismo
10.
Zootaxa ; 4392(2): 311-328, 2018 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-29690407

RESUMO

Glaciers and ice sheets are a peculiar biome with characteristic abiotic and biotic components. Mountain glaciers are predicted to decrease their volume and even to melt away within a few decades. Despite the threat of a disappearing biome, the diversity and the role of microscopic animals as consumers at higher trophic levels in the glacial biome still remain largely unknown. In this study, we report data on tardigrades and rotifers found in glacial mosses on Mount Stanley, Uganda, and describe a new tardigrade species. Adropion afroglacialis sp. nov. differs from the most similar species by having granulation on the cuticle, absence of cuticular bars under the claws, and a different macroplacoid length sequence. We also provide a morphological diagnosis for another unknown tardigrade species of the genus Hypsibius. The rotifers belonged to the families Philodinidae and Habrotrochidae. In addition, we discuss the diversity of microinvertebrates and potential role of tardigrades and rotifers on mountain glaciers as top consumers. As for any organism living apparently exclusively in glacial habitats on tropical glaciers, their extinction in the near future is inevitable, possibly before we can even discover their existence.


Assuntos
Rotíferos , Tardígrados , Animais , Briófitas , Camada de Gelo , Uganda
11.
FEMS Microbiol Ecol ; 92(9)2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27306554

RESUMO

Cryoconite granules are aggregations of microorganisms with mineral particles that form on glacier surfaces. To understand the processes by which the granules develop, this study focused on the altitudinal distribution of the granules and photosynthetic microorganisms on the glacier, bacterial community variation with granules size and environmental factors affecting the growth of the granules. Size-sorted cryoconite granules collected from five different sites on Qaanaaq Glacier were analyzed. C and N contents were significantly higher in large (diameter greater than 250 µm) granules than in smaller (diameter 30-249 µm) granules. Bacterial community structures, based on 16S rRNA gene amplicon sequencing, were different between the smaller and larger granules. The filamentous cyanobacterium Phormidesmis priestleyi was the dominant bacterial species in larger granules. Multivariate analysis suggests that the abundance of mineral particles on the glacier surface is the main factor controlling growth of these cyanobacteria. These results show that the supply of mineral particles on the glacier enhances granule development, that P. priestleyi is likely the key species for primary production and the formation of the granules and that the bacterial community in the granules changes over the course of the granule development.


Assuntos
Bactérias/isolamento & purificação , Camada de Gelo , Bactérias/genética , Cianobactérias/genética , Cianobactérias/isolamento & purificação , Groenlândia , Camada de Gelo/química , Camada de Gelo/microbiologia , Minerais , RNA Ribossômico 16S/genética
12.
PLoS One ; 9(11): e112510, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25401789

RESUMO

Tropical regions are not well represented in glacier biology, yet many tropical glaciers are under threat of disappearance due to climate change. Here we report a novel biogenic aggregation at the terminus of a glacier in the Rwenzori Mountains, Uganda. The material was formed by uniseriate protonemal moss gemmae and protonema. Molecular analysis of five genetic markers determined the taxon as Ceratodon purpureus, a cosmopolitan species that is widespread in tropical to polar region. Given optimal growing temperatures of isolate is 20-30 °C, the cold glacier surface might seem unsuitable for this species. However, the cluster of protonema growth reached approximately 10 °C in daytime, suggesting that diurnal increase in temperature may contribute to the moss's ability to inhabit the glacier surface. The aggregation is also a habitat for microorganisms, and the disappearance of this glacier will lead to the loss of this unique ecosystem.


Assuntos
Briófitas , Ecossistema , Camada de Gelo , Briófitas/classificação , Briófitas/genética , Briófitas/metabolismo , Geografia , Fenótipo , Fotossíntese , Uganda
13.
FEMS Microbiol Ecol ; 82(2): 279-86, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22304437

RESUMO

Psychrophilic yeasts have been isolated from supra- and subglacial ice at many sites worldwide. To understand the ecology of psychrophilic yeasts on glaciers, we focused on their adaptation to wide range of nutrient concentrations and their distribution with altitude on the Gulkana Glacier in Alaska. We found various culturable psychrophilic yeasts on the ice surfaces of the glacier, and 11 species were isolated with incubation at 4 °C in four different dilutions of agar medium. Some of our isolated species (Rhodotorula psychrophenolica, Rhodotorula aff. psychrophenolica, Rhodotorula glacialis, and Basidiomycota sp. 1) can grow on the low dissolved organic matter (DOC) concentrations medium (7.6 mg L(-1)) which is close to the typical level of supraglacial melt water, suggesting that these species can inhabit in any supraglacial meltwater. Otherwise, most of other species were isolated only from higher DOC concentration medium (183 mg L(-1) -18.3 g L(-1)), suggesting that these are inhabitant around the cryoconite, because DOC concentrations in melted surface-ice contained cryoconite is much higher than in melted water. Similarity of altitudinal distribution between culturable yeast and algal biomass suggests that the ecological role played by the cold-adapted yeasts is as organic matter decomposers and nutrient cyclers in glacier ecosystem.


Assuntos
Altitude , Basidiomycota/isolamento & purificação , Ecossistema , Camada de Gelo/microbiologia , Rhodotorula/isolamento & purificação , Alaska , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Filogenia , Rhodotorula/genética , Rhodotorula/crescimento & desenvolvimento
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