Tag: 16S rRNA

Reports

Microbial diversity in hot springs in Vonarskarð / Microbial diversity in hot springs in Vonarskarð

Published:

01/03/2009

Authors:

Sólveig K. Pétursdóttir, Snædís H. Björnsdóttir, Sólveig Ólafsdóttir, Guðmundur Óli Hreggviðsson

Supported by:

Orkustofnun due to the Master Plan

Contact

Guðmundur Óli Hreggviðsson

Strategic Scientist

gudmundo@matis.is

Microbial diversity in hot springs in Vonarskarð / Microbial diversity in hot springs in Vonarskarð

Samples were taken in the geothermal area east of Eggja in Vonarskarð. A total of 32 samples were taken from different hot springs, streams and soils at different temperatures and acidity levels. Elements were measured in several water samples. The species composition of bacteria and ancient bacteria was determined by molecular biological methods. A total of 1052 16S rRNA gene sequences of bacteria were detected, spreading across 23 factions. More than 50 new bacterial species were found in the samples, of which 11 are probably representatives of new genera. The genome of ancient bacteria was 155 in number. Ten new species of ancient bacteria were found, including five representatives of new genera. The ecosystem of the geothermal area as a whole must therefore be considered very special. The most common were the primitive species of the array Aquificae. Primitive and non-primitive Proteobacteria species were found in significant quantities and were both known and new species. Typical species of bluish-green bacteria and Chloroflexi were found in the samples. Firmicutes, Bacteroidetes and Chlorobi species were found mainly in samples taken at lower temperatures. Ancient bacteria found in the samples were spread over two largest groups of ancient bacteria, i.e. Crenarcheota and Euryarchaeota. The biological diversity of bacteria and archaeal bacteria in the samples was most often in the range Nt / Nmax = 1.0 -3.0, which is typical of peripheral ecosystems. In some cases it was higher, especially in samples where the temperature was relatively low and therefore more viable for more species. Seven bacterial species were cultured from the samples, including one new species of the genus Sediminibacter from the Bacteroidetes class. Several Thermus species were bred, including T.islandicus which is native to Iceland. The proteobacteria Thermomonas hydrothermalis and Tepidimonas ignava were also grown from several samples and the thermophilic Firmicutes species Anoxybacillus kualawohkensis.

Samples were taken from the geothermal area east of Eggja in Vonarskarð. A total of 32 samples were collected from different sites at various temperature and pH values. The concentration of 72 elements were estimated in water samples. Species composition of Bacteria and Archaea was estimated using molecular methods. A total of 1052 16S rRNA gene sequences belonging to 23 bacterial phyla were detected. Roughly 50 novel bacterial species were found of which 11 represent new genera. Ten novel archaeal species were found, five of which represent new genera. Species belonging to the autotrophic phylum of Aquificae dominated many samples. Species of different subphyla of Proteobacteria were also represented in high ratios in the samples, both described and novel species. Common species of Cyanobacteria and Chloroflexi were also detected. Species of the Firmicutes, Bacteroidetes and Chlorobi phyla were common in samples taken at lower temperatures. Archaeal species in the samples belonged to both Crenarchaeota and Euryarchaeota. The calculated biodiversity index for bacteria and archaea in the samples was 1,0-3,0 which is in concordance with values obtained for extreme ecosystems. It was higher in a few samples which were taken at lower temperatures and thus represent habitats acceptable for more diverse organisms. Seven bacterial species were isolated from the samples. One of these represents a novel species of the genus Sediminibacter within the phylum of Bacteroidetes. Several Thermus species were cultivated, ie T.islandicus which has so far only been found in Iceland. The Proteobacteria species Themomonas hydrothermalis and Tepidimonas ignava were also isolated as well as a thermophilic Firmicutes species, Anoxybacillus kualawohkensis.

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Reports

Lífríki í kalkríkum hverum á Ölkelduháls / Microbial ecology of calcium rich hot springs at Ölkelduháls geothermal area

Published:

01/10/2008

Authors:

Sólveig K. Pétursdóttir, Snædís Björnsdóttir, Alexandra Klonowski, Sólveig Ólafsdóttir, Guðmundur Óli Hreggviðsson

Supported by:

The Environmental and Energy Research Fund of Orkuveita Reykjavíkur

Contact

Alexandra María Klonowski

Project Manager

alex@matis.is

Lífríki í kalkríkum hverum á Ölkelduháls / Microbial ecology of calcium rich hot springs at Ölkelduháls geothermal area

The ecology of calcareous hot springs is little studied. This study involved analyzing the ecosystem in calcareous hot springs at Ölkelduháls and assessing whether it had a special position compared to the ecosystem of other hot springs in the same area with the same temperature and acidity. Bacteria were isolated from thermal samples by conventional culture methods. Genetic analysis methods were used to analyze the species composition. Many species found in samples from calcareous hot springs are also found in other hot springs. It is noteworthy, however, that species within the Aquificae party were not found in the samples, but they are very common in hot springs and widely prevalent. Elemental measurements showed differences in the concentration of sulfur, iron, carbon and arsenic in calcareous water and other hot springs, which may be an explanation for this. Cultivated methods identified mainly known bacterial species of the genera Thermus and Bacillus. One new species of the Meiothermus genus was isolated. Using genetic analysis methods, 195 true bacterial clones were obtained from calcareous hot springs, which were classified into 60 species based on 98% affinity. These 60 species are spread over nine camps. The species found in the samples were the same between the hot springs, but also unique to the sample from which they came. No ancient bacteria were found in the samples. Biodiversity in samples from calcareous hot springs at Ölkelduháls was slightly higher than comparable values from hot springs with similar properties in the same area. The high proportion of unknown species and genera in samples taken in calcareous hot springs at Ölkelduháls is noteworthy. Of the 60 species found in the samples, a sufficiently close relative of the same species was found in 25 cases. The other 35 species were so closely related to close relatives that they could not be classified except into genera, tribes, clans, or families. Ecosystems in calcareous hot springs at Ölkelduháls must therefore be considered very special.

The ecology of calcium rich hot springs is not well documented. In this study an attempt was made to estimate if microbial species composition in calcium rich hot springs in Ölkelduháls in Iceland was special compared to species composition in other hot springs with similar temperature and pH in the same geothermal area. Isolation methods as well as culture independent methods were used to analyze species composition in the samples. Many species found in the calcium rich hot springs are also found in other hot springs. It is noteworthy that Aquificae species were totally absent in samples from calcium rich hot springs, but these species were abundant and dominating in other hot spring samples. Elemental analysis of hot spring water revealed a difference in the concentration of sulfur, iron, carbon and arsenate between calcium rich hot springs and other hot springs in the area. Known species of Thermus and Bacillus genera were isolated from the samples. A novel Meiothermus species was isolated. Approximately 60 species belonging to nine phyla were identified in the samples using culture independent methods. The species identified in the calcium rich samples were identical between samples but also unique for the sample investigated. No archaea were detected in the samples. Biodiversity calculated for the samples from calcium rich hot springs was slightly higher than in samples from other hot springs. A high ratio of unknown species and genera in the samples from calcium rich hot springs in Ölkelduháls is remarkable. Of the total of 60 species identified only 25 had a close relative from the same species according to Genbank. The remaining 35 species were only distantly related to their closest relative and could only be classified to genera, families, orders or classes. Thus, the ecology of calcium rich hot springs appears to be quite unique.

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Reports

Biodiversity in hot springs in Krísuvík and Gunnuhver in Reykjanes: Research carried out due to the Framework Plan for the utilization of geothermal energy in high-temperature areas

Published:

01/08/2007

Authors:

Sólveig K. Pétursdóttir, Sólveig Ólafsdóttir, Steinunn Magnúsdóttir, Guðmundur Óli Hreggviðsson

Contact

Steinunn Ásbjörg Magnúsdóttir

Project Manager

steinunn.magnusdottir@matis.is

Biodiversity in hot springs in Krísuvík and Gunnuhver in Reykjanes: Research carried out due to the Framework Plan for the utilization of geothermal energy in high-temperature areas

This study of the ecosystem in the hot springs in the Krísuvík area is the third biota assessment carried out within the Framework Program, but the first two dealt with the ecosystem in the hot springs in the Hengill area and in the Torfajökull area.

Emphasis was placed on the thermal area in Seltún, where sampling was joint with the geochemists of the Institute of Earth Sciences, which was the first step in an interdisciplinary approach to the subject, which is hoped for, but is still in its early stages. Other areas that were tried to explore were hot springs by Austurengjahver and the area by Gunnuhver in Reykjanes. The temperature in the hot springs in Seltún was in the range of 53-93 ° C and furthermore one soil sample was reported which was taken at a lower temperature or 34 ° C. The acidity of the hot springs in Seltún was in the range of pH 2.5-6. The temperature in the hot springs at Austurengjahver was between 50-75 ° C and the pH pH 2.4 - 4.3. The temperature in the hot springs at Gunnuhver was measured in the range of 70-90 ° C and the pH pH 3.8 - 4.2. A total of thirteen samples were taken in the above areas and DNA was successfully isolated from seven of them. DNA could not be extracted from the samples at Austurengjahver. Nucleic acid amplification of the 16S rRNA, a species-differentiating gene of the nuclear nucleus, was performed on six samples. Amplification was obtained from all these samples with specific real bacterial indicators, but three with ancient bacterial indicators.

A total of 304 sequences of real bacterial species were obtained in the area known as Seltún. These species are spread over 26 species which in turn are spread over 10 camps. The primitive species of the Aquificeae array house over 80% sequences and are therefore predominant in these samples and are primary producers in the ecosystems of the hot springs. Five species within this array were found in the samples from Seltún. Other species are mainly classified into different groups Proteobacteria (13%) but they are a very diverse group. Other species found are sparsely populated and less important here. A total of 81 sequences of ancient bacterial species were obtained from the Seltún area. Most of them or space 90% are classified as Thermoplasmatales within the Euryarchaeota class, but this is a heat and acid species. Other ancient bacteria in the samples in Seltún belong to the Chrenarchaeota group, mostly to the genus Desulfurococcales.

A total of 56 actual bacterial differentiations were obtained from the hot springs at Gunnuhver. The vast majority of them (about 70%) belong to the primitive class Aquificeae, but about 30% to different groups of Proteobacteria. The ancient bacteria in Gunnuhver are homogeneous as they are all of the genus Sulfolobales which is a very heat and acid group. 1 Overall, it can be said that the area around Seltún shows a typical pattern of a peripheral ecosystem where one species is predominant and other species are spread over various factions. The calculated biodiversity in the samples was relatively low or in the range of 1.0-2.0. For comparison, the same coefficient calculated for samples from the Torfajökull area and at Ölkelduháls was in the range of 1.1-4.7. The environmental conditions of temperature and acidity in Seltún and Gunnuhver are not on the edge, but it is likely that substances and compounds in the hot springs and clay can affect the diversity of the ecosystem, ie. which species get thrive and which do not.

Rare species that had only distant relatives in Genbank were found in the Seltún samples, among others. In most cases, however, there are only 1-2 representatives of the species in question. Most of these distantly related species were classified as Proteobacteria and Acidobacteria.

Matís - Prokaria will probably continue to work on sampling and species analysis in the Krísuvík area. The intention is to include these results in a final summary of the ecosystem in hot springs in Iceland in the last year of the Framework Program.

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