scholarly journals Habitat generalists or specialists, insights from comparative genomic analyses of Thermosipho lineages

2017 ◽  
Author(s):  
Thomas H.A. Haverkamp ◽  
Claire Geslin ◽  
Julien Lossouarn ◽  
Olga A. Podosokorskaya ◽  
Ilya Kublanov ◽  
...  
Keyword(s):  
Hydrothermal Vents ◽  
Hot Springs ◽  
Extreme Environments ◽  
Petroleum Reservoirs ◽  
Comparative Genomic ◽  
Mobile Dna ◽  
Genomic Analyses ◽  
Habitat Differentiation ◽  
Terrestrial Hot Springs ◽  
Habitat Generalists

AbstractThermosipho species inhabit various extreme environments such as marine hydrothermal vents, petroleum reservoirs and terrestrial hot springs. A 16S rRNA phylogeny of available Thermosipho spp. sequences suggested habitat specialists adapted to living in hydrothermal vents only, and habitat generalists inhabiting oil reservoirs, hydrothermal vents and hotsprings. Comparative genomics and recombination analysis of the genomes of 15 Thermosipho isolates separated them into three species with different habitat distributions, the widely distributed T. africanus and the more specialized, T. melanesiensis and T. affectus. The three Thermosipho species can also be differentiated on the basis of genome content. For instance the T. africanus genomes had the largest repertoire of carbohydrate metabolism, which could explain why these isolates were obtained from ecologically more divergent habitats. The three species also show different capacities for defense against foreign DNA. T. melanesiensis and T. africanus both had a complete RM system, while this was missing in T. affectus. These observations also correlated with Pacbio sequencing, which revealed a methylated T. melanesiensis BI431 genome, while no methylation was detected among two T. affectus isolates. All the genomes carry CRISPR arrays accompanied by more or less complete CRISPR-cas systems. Interestingly, some isolates of both T. melanesiensis and T. africanus carry integrated prophage elements, with spacers matching these in their CRISPR arrays. Taken together, the comparative genomic analyses of Thermosipho spp. revealed genetic variation allowing habitat differentiation within the genus as well as differentiation with respect to invading mobile DNA that is present in subsurface ecosystems.

scholarly journals Thermosipho spp. immune system differences affect variation in genome size and geographical distributions

2018 ◽  
Author(s):  
Thomas H.A. Haverkamp ◽  
Claire Geslin ◽  
Julien Lossouarn ◽  
Olga A. Podosokorskaya ◽  
Ilya Kublanov ◽  
...  
Keyword(s):  
Immune System ◽  
Genome Size ◽  
Hydrothermal Vents ◽  
Hot Springs ◽  
Distinct Species ◽  
Mobile Elements ◽  
Comparative Genomic ◽  
Type I ◽  
Mobile Dna ◽  
Thermal Environments

AbstractThermosipho species inhabit thermal environments such as marine hydrothermal vents, petroleum reservoirs and terrestrial hot springs. A 16S rRNA phylogeny of available Thermosipho spp. sequences suggested habitat specialists adapted to living in hydrothermal vents only, and habitat generalists inhabiting oil reservoirs, hydrothermal vents and hotsprings. Comparative genomics of 15 Thermosipho genomes separated them into three distinct species with different habitat distributions: the widely distributed T. africanus and the more specialized, T. melanesiensis and T. affectus. Moreover, the species can be differentiated on the basis of genome size, genome content and immune system composition. For instance, the T. africanus genomes are largest and contained the most carbohydrate metabolism genes, which could explain why these isolates were obtained from ecologically more divergent habitats. Nonetheless, all the Thermosipho genomes, like other Thermotogae genomes, show evidence of genome streamlining. Genome size differences between the species could further be correlated to differences in defense capacities against foreign DNA, which influence recombination via HGT. The smallest genomes are found in T. affectus that contain both CRISPR-cas Type I and III systems, but no RM system genes. We suggest that this has caused these genomes to be almost devoid of mobile elements, contrasting the two other species genomes that contain a higher abundance of mobile elements combined with different immune system configurations. Taken together, the comparative genomic analyses of Thermosipho spp. revealed genetic variation allowing habitat differentiation within the genus as well as differentiation with respect to invading mobile DNA.

scholarly journals Extremophilic Exopolysaccharides: Biotechnologies and Wastewater Remediation

2021 ◽  
Vol 12 ◽  
Author(s):  
Aparna Banerjee ◽  
Shrabana Sarkar ◽  
Tanvi Govil ◽  
Patricio González-Faune ◽  
Gustavo Cabrera-Barjas ◽  
...  
Keyword(s):  
Hydrothermal Vents ◽  
Hot Springs ◽  
Mine Drainage ◽  
Oil Spills ◽  
Extreme Environments ◽  
Substantial Part ◽  
Wastewater Remediation ◽  
Water Contaminants ◽  
Chemical Groups ◽  
Trace And Toxic Metals

Various microorganisms thrive under extreme environments, like hot springs, hydrothermal vents, deep marine ecosystems, hyperacid lakes, acid mine drainage, high UV exposure, and more. To survive against the deleterious effect of these extreme circumstances, they form a network of biofilm where exopolysaccharides (EPSs) comprise a substantial part. The EPSs are often polyanionic due to different functional groups in their structural backbone, including uronic acids, sulfated units, and phosphate groups. Altogether, these chemical groups provide EPSs with a negative charge allowing them to (a) act as ligands toward dissolved cations as well as trace, and toxic metals; (b) be tolerant to the presence of salts, surfactants, and alpha-hydroxyl acids; and (c) interface the solubilization of hydrocarbons. Owing to their unique structural and functional characteristics, EPSs are anticipated to be utilized industrially to remediation of metals, crude oil, and hydrocarbons from contaminated wastewaters, mines, and oil spills. The biotechnological advantages of extremophilic EPSs are more diverse than traditional biopolymers. The present review aims at discussing the mechanisms and strategies for using EPSs from extremophiles in industries and environment bioremediation. Additionally, the potential of EPSs as fascinating biomaterials to mediate biogenic nanoparticles synthesis and treat multicomponent water contaminants is discussed.

Magnetotactic bacteria in Tengchong hot springs, China

2020 ◽  
Author(s):  
Jia Liu ◽  
Wensi Zhang ◽  
Fang Yuan ◽  
Yongxin Pan ◽  
Wei Lin
Keyword(s):  
Hot Springs ◽  
Hot Spring ◽  
Extreme Environments ◽  
Magnetotactic Bacteria ◽  
Origin And Evolution ◽  
Water Columns ◽  
Genomic Analyses ◽  
Ph Range ◽  
Identification And Characterization

<p>Magnetotactic bacteria (MTB) biomineralize intracellular magnetic nanocrystals and can use the geomagnetic field to navigate towards specific microenvironments in water columns and sediments. MTB are a model system to study the mechanisms of microbial magnetoreception and biomineralization. The majority of MTB identified so far are from environments with pH values near neutral and at the normal range of temperature. MTB from extreme environments, such as hot springs, has not been observed and described until recently. However, our knowledge on extremophilic MTB is still very limited. Here we report the identification and characterization of various MTB in Tengchong hot springs, China, with a temperature range of 41.3-69.5 °C and a pH range of 7.1-8.6. Although MTB are diverse in cell morphology, they all form bullet-shaped magnetite magnetosomes organized into either one chain or multiple bundles of chains. Through genome-resolved metagenomics, we have reconstructed five genome bins of hot spring MTB that are all affiliated within the <em>Nitrspirae</em> phylum. Genomic analyses and metabolic reconstructions are now in progress. These results will help to better understand the extremophilic MTB and may shed new lights on the origin and evolution of microbial magnetoreception and biomineralization.</p>

scholarly journals Genome of the bi-annual Rio Pearlfish (Nematolebias whitei), a killifish model species for Eco-Evo-Devo

2021 ◽  
Author(s):  
Andrew W. Thompson ◽  
Harrison Wojtas ◽  
Myles Davoll ◽  
Ingo Braasch
Keyword(s):  
Life Histories ◽  
Developmental Stages ◽  
Genome Structure ◽  
Extreme Environments ◽  
Comparative Genomic ◽  
Gene Repertoire ◽  
Mobile Dna ◽  
Model Species ◽  
D Genome ◽  
Evo Devo

The Rio Pearlfish Nematolebias whitei is a bi-annual killifish species inhabiting seasonal pools of the Rio de Janeiro region that dry twice per year. Embryos enter dormant diapause stages in the soil, waiting for the inundation of the habitat which triggers hatching and commencement of a new life cycle. This species represents a convergent, independent origin of annualism from other emerging killifish model species. While some transcriptomic datasets are available for Rio Pearlfish, thus far a sequenced genome has been unavailable. Here we present a high quality, 1.2Gb chromosome-level genome assembly, genome annotations and a comparative genomic investigation of the Rio Pearlfish as representative of a vertebrate clade that evolved environmentally-cued hatching. We show conservation of 3-D genome structure across teleost fish evolution, developmental stages, tissues and cell types. Our analysis of mobile DNA shows that Rio Pearlfish, like other annual killifishes, possesses an expanded transposable element profile with implications for rapid aging and adaptation to harsh conditions. We use the Rio Pearlfish genome to identify its hatching enzyme gene repertoire and the location of the hatching gland, a key first step in understanding the developmental genetic control of hatching. The Rio Pearlfish genome expands the comparative genomic toolkit available to study convergent origins of seasonal life histories, diapause, and rapid aging phenotypes. We present the first set of genomic resources for this emerging model organism, critical for future functional genetic and multi-omic explorations of Eco-Evo-Devo phenotypes in resilience and adaptation to extreme environments.

scholarly journals Genome sequencing of deep-sea hydrothermal vent snails reveals adaptions to extreme environments

GigaScience ◽  
2020 ◽  
Vol 9 (12) ◽  
Author(s):  
Xiang Zeng ◽  
Yaolei Zhang ◽  
Lingfeng Meng ◽  
Guangyi Fan ◽  
Jie Bai ◽  
...  
Keyword(s):  
Genome Sequencing ◽  
Deep Sea ◽  
Hydrothermal Vents ◽  
Extreme Environments ◽  
Genomic Analysis ◽  
Gene Families ◽  
Comparative Genomic ◽  
Limited Information ◽  
Long Terminal Repeats ◽  
Family Analysis

Abstract Background The scaly-foot snail (Chrysomallon squamiferum) is highly adapted to deep-sea hydrothermal vents and has drawn much interest since its discovery. However, the limited information on its genome has impeded further related research and understanding of its adaptation to deep-sea hydrothermal vents. Findings Here, we report the whole-genome sequencing and assembly of the scaly-foot snail and another snail (Gigantopelta aegis), which inhabits similar environments. Using Oxford Nanopore Technology, 10X Genomics, and Hi-C technologies, we obtained a chromosome-level genome of C. squamiferum with an N50 size of 20.71 Mb. By constructing a phylogenetic tree, we found that these 2 deep-sea snails evolved independently of other snails. Their divergence from each other occurred ∼66.3 million years ago. Comparative genomic analysis showed that different snails have diverse genome sizes and repeat contents. Deep-sea snails have more DNA transposons and long terminal repeats but fewer long interspersed nuclear elements than other snails. Gene family analysis revealed that deep-sea snails experienced stronger selective pressures than freshwater snails, and gene families related to the nervous system, immune system, metabolism, DNA stability, antioxidation, and biomineralization were significantly expanded in scaly-foot snails. We also found 251 H-2 Class II histocompatibility antigen, A-U α chain-like (H2-Aal) genes, which exist uniquely in the Gigantopelta aegis genome. This finding is important for investigating the evolution of major histocompatibility complex (MHC) genes. Conclusion Our study provides new insights into deep-sea snail genomes and valuable resources for further studies.

Archaeal habitats — from the extreme to the ordinary

2006 ◽  
Vol 52 (2) ◽  
pp. 73-116 ◽  
Author(s):  
Bonnie Chaban ◽  
Sandy Y.M Ng ◽  
Ken F Jarrell
Keyword(s):  
Hydrothermal Vents ◽  
Hot Springs ◽  
Soda Lakes ◽  
Carbon Sources ◽  
Extreme Environments ◽  
Molecular Techniques ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Extreme Halophiles ◽  
Uncultured Archaea

The domain Archaea represents a third line of evolutionary descent, separate from Bacteria and Eucarya. Initial studies seemed to limit archaea to various extreme environments. These included habitats at the extreme limits that allow life on earth, in terms of temperature, pH, salinity, and anaerobiosis, which were the homes to hyper thermo philes, extreme (thermo)acidophiles, extreme halophiles, and methanogens. Typical environments from which pure cultures of archaeal species have been isolated include hot springs, hydrothermal vents, solfataras, salt lakes, soda lakes, sewage digesters, and the rumen. Within the past two decades, the use of molecular techniques, including PCR-based amplification of 16S rRNA genes, has allowed a culture-independent assessment of microbial diversity. Remarkably, such techniques have indicated a wide distribution of mostly uncultured archaea in normal habitats, such as ocean waters, lake waters, and soil. This review discusses organisms from the domain Archaea in the context of the environments where they have been isolated or detected. For organizational purposes, the domain has been separated into the traditional groups of methanogens, extreme halophiles, thermoacidophiles, and hyperthermophiles, as well as the uncultured archaea detected by molecular means. Where possible, we have correlated known energy-yielding reactions and carbon sources of the archaeal types with available data on potential carbon sources and electron donors and acceptors present in the environments. From the broad distribution, metabolic diversity, and sheer numbers of archaea in environments from the extreme to the ordinary, the roles that the Archaea play in the ecosystems have been grossly underestimated and are worthy of much greater scrutiny.Key words: Archaea, methanogen, extreme halophile, hyperthermophile, thermoacidophile, uncultured archaea, habitats.

scholarly journals Factors Controlling the Distribution of Archaeal Tetraethers in Terrestrial Hot Springs

2008 ◽  
Vol 74 (11) ◽  
pp. 3523-3532 ◽  
Author(s):  
Ann Pearson ◽  
Yundan Pi ◽  
Weidong Zhao ◽  
WenJun Li ◽  
Yiliang Li ◽  
...  
Keyword(s):  
United States ◽  
Great Basin ◽  
Hot Springs ◽  
Extreme Environments ◽  
Principal Component ◽  
Archaeal Community ◽  
Wide Distribution ◽  
Pure Cultures ◽  
Terrestrial Hot Springs ◽  
Archaeal Communities

ABSTRACT Glycerol dialkyl glycerol tetraethers (GDGTs) found in hot springs reflect the abundance and community structure of Archaea in these extreme environments. The relationships between GDGTs, archaeal communities, and physical or geochemical variables are underexamined to date and when reported often result in conflicting interpretations. Here, we examined profiles of GDGTs from pure cultures of Crenarchaeota and from terrestrial geothermal springs representing a wide distribution of locations, including Yellowstone National Park (United States), the Great Basin of Nevada and California (United States), Kamchatka (Russia), Tengchong thermal field (China), and Thailand. These samples had temperatures of 36.5 to 87°C and pH values of 3.0 to 9.2. GDGT abundances also were determined for three soil samples adjacent to some of the hot springs. Principal component analysis identified four factors that accounted for most of the variance among nine individual GDGTs, temperature, and pH. Significant correlations were observed between pH and the GDGTs crenarchaeol and GDGT-4 (four cyclopentane rings, m/z 1,294); pH correlated positively with crenarchaeol and inversely with GDGT-4. Weaker correlations were observed between temperature and the four factors. Three of the four GDGTs used in the marine TEX86 paleotemperature index (GDGT-1 to -3, but not crenarchaeol isomer) were associated with a single factor. No correlation was observed for GDGT-0 (acyclic caldarchaeol): it is effectively its own variable. The biosynthetic mechanisms and exact archaeal community structures leading to these relationships remain unknown. However, the data in general show promise for the continued development of GDGT lipid-based physiochemical proxies for archaeal evolution and for paleo-ecology or paleoclimate studies.

scholarly journals The domestication of Cucurbita argyrosperma as revealed by the genome of its wild relative

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Josué Barrera-Redondo ◽  
Guillermo Sánchez-de la Vega ◽  
Jonás A. Aguirre-Liguori ◽  
Gabriela Castellanos-Morales ◽  
Yocelyn T. Gutiérrez-Guerrero ◽  
...  
Keyword(s):  
Defense Mechanisms ◽  
Population Level ◽  
Growth Hormones ◽  
Comparative Genomic ◽  
Structural Variants ◽  
Closely Related Species ◽  
Level Data ◽  
Genomic Analyses ◽  
Genotype By Sequencing ◽  
Regulation Of Growth

AbstractDespite their economic importance and well-characterized domestication syndrome, the genomic impact of domestication and the identification of variants underlying the domestication traits in Cucurbita species (pumpkins and squashes) is currently lacking. Cucurbita argyrosperma, also known as cushaw pumpkin or silver-seed gourd, is a Mexican crop consumed primarily for its seeds rather than fruit flesh. This makes it a good model to study Cucurbita domestication, as seeds were an essential component of early Mesoamerican diet and likely the first targets of human-guided selection in pumpkins and squashes. We obtained population-level data using tunable Genotype by Sequencing libraries for 192 individuals of the wild and domesticated subspecies of C. argyrosperma across Mexico. We also assembled the first high-quality wild Cucurbita genome. Comparative genomic analyses revealed several structural variants and presence/absence of genes related to domestication. Our results indicate a monophyletic origin of this domesticated crop in the lowlands of Jalisco. We found evidence of gene flow between the domesticated and wild subspecies, which likely alleviated the effects of the domestication bottleneck. We uncovered candidate domestication genes that are involved in the regulation of growth hormones, plant defense mechanisms, seed development, and germination. The presence of shared selected alleles with the closely related species Cucurbita moschata suggests domestication-related introgression between both taxa.

Complete chloroplast genomes of Leptodermis scabrida complex: comparative genomic analyses and phylogenetic relationships

Gene ◽  
2021 ◽  
pp. 145715
Author(s):  
Ying Zhang ◽  
Zhengfeng Wang ◽  
Yanan Guo ◽  
Sheng Chen ◽  
Xianyi Xu ◽  
...  
Keyword(s):  
Phylogenetic Relationships ◽  
Comparative Genomic ◽  
Chloroplast Genomes ◽  
Genomic Analyses

scholarly journals Microbial Diversity of Terrestrial Geothermal Springs in Armenia and Nagorno-Karabakh: A Review

2021 ◽  
Vol 9 (7) ◽  
pp. 1473
Author(s):  
Ani Saghatelyan ◽  
Armine Margaryan ◽  
Hovik Panosyan ◽  
Nils-Kåre Birkeland
Keyword(s):  
16S Rrna ◽  
Microbial Diversity ◽  
High Altitude ◽  
Hot Springs ◽  
Hot Spring ◽  
Abiotic Factors ◽  
Rrna Gene ◽  
Geothermal Springs ◽  
Bacterial Phyla ◽  
Terrestrial Hot Springs

The microbial diversity of high-altitude geothermal springs has been recently assessed to explore their biotechnological potential. However, little is known regarding the microbiota of similar ecosystems located on the Armenian Highland. This review summarizes the known information on the microbiota of nine high-altitude mineralized geothermal springs (temperature range 25.8–70 °C and pH range 6.0–7.5) in Armenia and Nagorno-Karabakh. All these geothermal springs are at altitudes ranging from 960–2090 m above sea level and are located on the Alpide (Alpine–Himalayan) orogenic belt, a seismically active region. A mixed-cation mixed-anion composition, with total mineralization of 0.5 mg/L, has been identified for these thermal springs. The taxonomic diversity of hot spring microbiomes has been examined using culture-independent approaches, including denaturing gradient gel electrophoresis (DGGE), 16S rRNA gene library construction, 454 pyrosequencing, and Illumina HiSeq. The bacterial phyla Proteobacteria, Bacteroidetes, Cyanobacteria, and Firmicutes are the predominant life forms in the studied springs. Archaea mainly include the phyla Euryarchaeota, Crenarchaeota, and Thaumarchaeota, and comprise less than 1% of the prokaryotic community. Comparison of microbial diversity in springs from Karvachar with that described for other terrestrial hot springs revealed that Proteobacteria, Bacteroidetes, Actinobacteria, and Deinococcus–Thermus are the common bacterial groups in terrestrial hot springs. Contemporaneously, specific bacterial and archaeal taxa were observed in different springs. Evaluation of the carbon, sulfur, and nitrogen metabolism in these hot spring communities has revealed diversity in terms of metabolic activity. Temperature seems to be an important factor in shaping the microbial communities of these springs. Overall, the diversity and richness of the microbiota are negatively affected by increasing temperature. Other abiotic factors, including pH, mineralization, and geological history, also impact the structure and function of the microbial community. More than 130 bacterial and archaeal strains (Bacillus, Geobacillus, Parageobacillus, Anoxybacillus, Paenibacillus, Brevibacillus Aeribacillus, Ureibacillus, Thermoactinomyces, Sporosarcina, Thermus, Rhodobacter, Thiospirillum, Thiocapsa, Rhodopseudomonas, Methylocaldum, Desulfomicrobium, Desulfovibrio, Treponema, Arcobacter, Nitropspira, and Methanoculleus) have been reported, some of which may be representative of novel species (sharing 91–97% sequence identity with their closest matches in GenBank) and producers of thermozymes and biomolecules with potential biotechnological applications. Whole-genome shotgun sequencing of T. scotoductus K1, as well as of the potentially new Treponema sp. J25 and Anoxybacillus sp. K1, were performed. Most of the phyla identified by 16S rRNA were also identified using metagenomic approaches. Detailed characterization of thermophilic isolates indicate the potential of the studied springs as a source of biotechnologically valuable microbes and biomolecules.

Sign in / Sign up

Export Citation Format

Share Document