scholarly journals Groundwater cable bacteria conserve energy by sulfur disproportionation

2019 ◽  
Vol 14 (2) ◽  
pp. 623-634 ◽  
Author(s):  
Hubert Müller ◽  
Sviatlana Marozava ◽  
Alexander J. Probst ◽  
Rainer U. Meckenstock
Keyword(s):  
16S Rrna ◽  
Electron Donor ◽  
Nitrate Reduction ◽  
Elemental Sulfur ◽  
Single Cells ◽  
Sulfur Oxidation ◽  
Metabolic Reconstruction ◽  
Rrna Gene ◽  
Long Distance ◽  
Sulfur Disproportionation

AbstractCable bacteria of the family Desulfobulbaceae couple spatially separated sulfur oxidation and oxygen or nitrate reduction by long-distance electron transfer, which can constitute the dominant sulfur oxidation process in shallow sediments. However, it remains unknown how cells in the anoxic part of the centimeter-long filaments conserve energy. We found 16S rRNA gene sequences similar to groundwater cable bacteria in a 1-methylnaphthalene-degrading culture (1MN). Cultivation with elemental sulfur and thiosulfate with ferrihydrite or nitrate as electron acceptors resulted in a first cable bacteria enrichment culture dominated >90% by 16S rRNA sequences belonging to the Desulfobulbaceae. Desulfobulbaceae-specific fluorescence in situ hybridization (FISH) unveiled single cells and filaments of up to several hundred micrometers length to belong to the same species. The Desulfobulbaceae filaments also showed the distinctive cable bacteria morphology with their continuous ridge pattern as revealed by atomic force microscopy. The cable bacteria grew with nitrate as electron acceptor and elemental sulfur and thiosulfate as electron donor, but also by sulfur disproportionation when Fe(Cl)2 or Fe(OH)3 were present as sulfide scavengers. Metabolic reconstruction based on the first nearly complete genome of groundwater cable bacteria revealed the potential for sulfur disproportionation and a chemo-litho-autotrophic metabolism. The presence of different types of hydrogenases in the genome suggests that they can utilize hydrogen as alternative electron donor. Our results imply that cable bacteria not only use sulfide oxidation coupled to oxygen or nitrate reduction by LDET for energy conservation, but sulfur disproportionation might constitute the energy metabolism for cells in large parts of the cable bacterial filaments.

scholarly journals Methanobacterium movens sp. nov. and Methanobacterium flexile sp. nov., isolated from lake sediment

2011 ◽  
Vol 61 (12) ◽  
pp. 2974-2978 ◽  
Author(s):  
Jinxing Zhu ◽  
Xiaoli Liu ◽  
Xiuzhu Dong
Keyword(s):  
Phylogenetic Analysis ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Strain ◽  
Qaidam Basin ◽  
Sequence Similarity ◽  
Single Cells ◽  
Rrna Gene ◽  
Qinghai Province ◽  
Gram Staining

Two mesophilic methanogenic strains, designated TS-2T and GHT, were isolated from sediments of Tuosu lake and Gahai lake, respectively, in the Qaidam basin, Qinghai province, China. Cells of both isolates were rods (about 0.3–0.5×2–5 µm) with blunt rounded ends and Gram-staining-positive. Strain TS-2T was motile with one or two polar flagella and used only H2/CO2 for growth and methanogenesis. Strain GHT was non-motile, used both H2/CO2 and formate and displayed a variable cell arrangement depending on the substrate: long chains when growing in formate (50 mM) or under high pressure H2 and single cells under low pressure H2. Phylogenetic analysis based on 16S rRNA gene sequences placed the two isolates in the genus Methanobacterium. Strain TS-2T was most closely related to Methanobacterium alcaliphilum NBRC 105226T (96 % 16S rRNA gene sequence similarity). Phylogenetic analysis based on the alpha subunit of methyl-coenzyme M reductase also supported the affiliation of the two isolates with the genus Methanobacterium. DNA–DNA relatedness between the isolates and M. alcaliphilum DSM 3387T was 39–53 %. Hence we propose two novel species, Methanobacterium movens sp. nov. (type strain TS-2T = AS 1.5093T = JCM 15415T) and Methanobacterium flexile sp. nov. (type strain GHT = AS 1.5092T = JCM 15416T).

scholarly journals Sulfurimonas xiamenensis sp. nov. and Sulfurimonas lithotrophica sp. nov., hydrogen- and sulfur-oxidizing chemolithoautotrophs within the Epsilonproteobacteria isolated from coastal sediments, and an emended description of the genus Sulfurimonas

2020 ◽  
Vol 70 (4) ◽  
pp. 2657-2663 ◽  
Author(s):  
Shasha Wang ◽  
Lijing Jiang ◽  
Xuewen Liu ◽  
Suping Yang ◽  
Zongze Shao
Keyword(s):  
Fatty Acids ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Species ◽  
Elemental Sulfur ◽  
Rrna Gene ◽  
16S Rrna Gene Sequences ◽  
Content Type ◽  
Link Type ◽  
Emended Description

Strains 1-1NT and GYSZ_1T were isolated from marine sediments collected from the coast of Xiamen, PR China. Cells of the two strains were Gram-stain-negative, rod-shaped or slightly curved. Strain 1-1NT was non-motile, whereas strain GYSZ_1T was motile by means of one polar flagellum. The temperature, pH and salinity concentration ranges for growth of 1-1NT were 10–45 °C (optimum 30 °C), pH 5.5–8.0 (optimum 7.0) and 0–90 g l−1 NaCl (optimum 50 g l−1), while the growth of GYSZ_1T occurred at 4–45 °C (optimum 33 °C), pH 5.0–8.5 (optimum 6.5) and 5–90 g l−1 NaCl (optimum 20 g l−1). The two novel isolates were obligate chemolithoautotrophs capable of growth using hydrogen, thiosulfate, sulfide or elemental sulfur as the sole energy source, and nitrate, elemental sulfur or molecular oxygen as an electron acceptor. The major fatty acids of 1-1NT were C16 : 1ω7c, C16 : 0, C18 : 1ω7c and C18 : 0, while the predominant fatty acids of strain GYSZ_1T were C16 : 1ω7c, C16 : 0, C18 : 1ω7c and C14 : 0 3-OH. The DNA G+C contents of 1-1NT and GYSZ_1T were 34.5 mol% and 33.2 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that 1-1NT and GYSZ_1T represented members of the genus Sulfurimonas , with the highest sequence similarities to Sulfurimonas crateris SN118T (97.4 %) and Sulfurimonas denitrificans DSM 1251T (94.7 %), respectively. However, 1-1NT and GYSZ_1T shared 95.5 % similarity of 16S rRNA gene sequences, representing different species of the genus Sulfurimonas . On the basis of the physiological properties and the results of phylogenetic analyses, including average nucleotide identity and in silico DNA–DNA hybridization values, strains 1-1NT and GYSZ_1T represent two novel species within the genus Sulfurimonas , for which the names Sulfurimonas xiamenensis sp. nov. and Sulfurimonas lithotrophica sp. nov. are proposed, with the type strains 1-1NT (=MCCC 1A14514T=KCTC 15851T) and GYSZ_1T (=MCCC 1A14739T=KCTC 15853T), respectively. Our results also justify an emended description of the genus Sulfurimonas .

scholarly journals Lysinibacillus varians sp. nov., an endospore-forming bacterium with a filament-to-rod cell cycle

2014 ◽  
Vol 64 (Pt_11) ◽  
pp. 3644-3649 ◽  
Author(s):  
Chunjie Zhu ◽  
Guoping Sun ◽  
Xingjuan Chen ◽  
Jun Guo ◽  
Meiying Xu
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Species ◽  
Sequence Similarity ◽  
Single Cells ◽  
Rrna Gene ◽  
Phylogenetic Distance ◽  
Content Type ◽  
Dna Relatedness ◽  
Link Type

Six Gram-stain-positive, motile, filamentous and/or rod-shaped, spherical spore-forming bacteria (strains GY32T, L31, F01, F03, F06 and F07) showing polybrominated diphenyl ether transformation were investigated to determine their taxonomic status. After spore germination, these organisms could grow more than one hundred microns long as intact single cells and then divide into rod cells and form endospores in 33 h. The cell-wall peptidoglycan of these strains was type A4α, the predominant menaquinone was MK-7 and the major fatty acids were iso-C16 : 0, iso-C15 : 0 and C16 : 1ω7C. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were detected in the polar lipid profile. Analysis of the 16S rRNA gene sequences indicated that these strains should be placed in the genus Lysinibacillus and they were most closely related to Lysinibacillus sphaericus DSM 28T (99 % 16S rRNA gene sequence similarity). The gyrB sequence similarity and DNA–DNA relatedness between strain GY32T and L. sphaericus JCM 2502T were 81 % and 52 %, respectively. The G+C content of the genomic DNA of strain GY32T was 43.2 mol%. In addition, strain GY32T showed differences in nitrate reduction, starch and gelatin hydrolysis, carbon resource utilization and cell morphology. The phylogenetic distance from its closest relative measured by DNA–DNA relatedness and DNA G+C content, and its phenotypic properties demonstrated that strain GY32T represents a novel species of the genus Lysinibacillus , for which the name Lysinibacillus varians sp. nov. is proposed. The type strain is GY32T ( = NBRC 109424T = CGMCC 1.12212T = CCTCC M 2011307T).

scholarly journals Sulfurihydrogenibium azorense, sp. nov., a thermophilic hydrogen-oxidizing microaerophile from terrestrial hot springs in the Azores

2004 ◽  
Vol 54 (1) ◽  
pp. 33-39 ◽  
Author(s):  
P. Aguiar ◽  
T. J. Beveridge ◽  
A.-L. Reysenbach
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Elemental Sulfur ◽  
Hot Springs ◽  
Rrna Gene ◽  
Temperature Growth ◽  
Likelihood Analysis ◽  
Distinct Lineage ◽  
Terrestrial Hot Springs ◽  
Rrna Phylogeny

Five hydrogen-oxidizing, thermophilic, strictly chemolithoautotrophic, microaerophilic strains, with similar (99–100 %) 16S rRNA gene sequences were isolated from terrestrial hot springs at Furnas, São Miguel Island, Azores, Portugal. The strain, designated Az-Fu1T, was characterized. The motile, 0·9–2·0 μm rods were Gram-negative and non-sporulating. The temperature growth range was from 50 to 73 °C (optimum at 68 °C). The strains grew fastest in 0·1 % (w/v) NaCl and at pH 6, although growth was observed from pH 5·5 to 7·0. Az-Fu1T can use elemental sulfur, sulfite, thiosulfate, ferrous iron or hydrogen as electron donors, and oxygen (0·2–9·0 %, v/v) as electron acceptor. Az-Fu1T is also able to grow anaerobically, with elemental sulfur, arsenate and ferric iron as electron acceptors. The Az-Fu1T G+C content was 33·6 mol%. Maximum-likelihood analysis of the 16S rRNA phylogeny placed the isolate in a distinct lineage within the Aquificales, closely related to Sulfurihydrogenibium subterraneum (2·0 % distant). The 16S rRNA gene of Az-Fu1T is 7·7 % different from that of Persephonella marina and 6·8 % different from Hydrogenothermus marinus. Based on the phenotypic and phylogenetic characteristics presented here, it is proposed that Az-Fu1T belongs to the recently described genus Sulfurihydrogenibium. It is further proposed that Az-Fu1T represents a new species, Sulfurihydrogenibium azorense.

scholarly journals Microbial community of recently discovered Auka vent field sheds light on vent biogeography and evolutionary history of thermophily

2021 ◽  
Author(s):  
Daan R Speth ◽  
Feiqiao B Yu ◽  
Stephanie A Connon ◽  
Sujung Lim ◽  
John S Magyar ◽  
...  
Keyword(s):  
Microbial Community ◽  
16S Rrna ◽  
Hydrothermal Vent ◽  
Gulf Of California ◽  
Hydrothermal Vents ◽  
Large Scale ◽  
Optimal Growth ◽  
Metabolic Reconstruction ◽  
Long Distance ◽  
The Pacific

Hydrothermal vents have been key to our understanding of the limits of life, and the metabolic and phylogenetic diversity of thermophilic organisms. Here we used environmental metagenomics combined with analysis of physico-chemical data and 16S rRNA amplicons to characterize the diversity, temperature optima, and biogeographic distribution of sediment-hosted microorganisms at the recently discovered Auka vents in the Gulf of California, the deepest known hydrothermal vent field in the Pacific Ocean. We recovered 325 metagenome assembled genomes (MAGs) representing 54 phyla, over 1/3 of the currently known phylum diversity, showing the microbial community in Auka hydrothermal sediments is highly diverse. Large scale 16S rRNA amplicon screening of 227 sediment samples across the vent field indicates that the MAGs are largely representative of the microbial community. Metabolic reconstruction of a vent-specific, deeply branching clade within the Desulfobacterota (Tharpobacteria) suggests these organisms metabolize sulfur using novel octaheme cytochrome-c proteins related to hydroxylamine oxidoreductase. Community-wide comparison of the average nucleotide identity of the Auka MAGs with MAGs from the Guaymas Basin vent field, found 400 km to the Northwest, revealed a remarkable 20% species-level overlap between vent sites, suggestive of long-distance species transfer and sediment colonization. An adapted version of a recently developed model for predicting optimal growth temperature to the Auka and Guaymas MAGs indicates several of these uncultured microorganisms could grow at temperatures exceeding the currently known upper limit of life. Extending this analysis to reference data shows that thermophily is a trait that has evolved frequently among Bacteria and Archaea. Combined, our results show that Auka vent field offers new perspectives on our understanding of hydrothermal vent microbiology.

Caldanaerobacter uzonensis sp. nov., an anaerobic, thermophilic, heterotrophic bacterium isolated from a hot spring

2010 ◽  
Vol 60 (6) ◽  
pp. 1372-1375 ◽  
Author(s):  
Irina V. Kozina ◽  
Ilya V. Kublanov ◽  
Tatyana V. Kolganova ◽  
Nikolai A. Chernyh ◽  
Elizaveta A. Bonch-Osmolovskaya
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Elemental Sulfur ◽  
Hot Spring ◽  
Novel Species ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
The Novel ◽  
Rrna Gene Sequence

An anaerobic thermophilic bacterium, strain K67T, was isolated from a terrestrial hot spring of Uzon Caldera, Kamchatka Peninsula. Analysis of the 16S rRNA gene sequence revealed that the novel isolate belongs to the genus Caldanaerobacter, with 95 % 16S rRNA gene sequence similarity to Caldanaerobacter subterraneus subsp. subterraneus SEBR 7858T, suggesting that it represents a novel species of the genus Caldanaerobacter. Strain K67T was characterized as an obligate anaerobe, a thermophile (growth at 50–75 °С; optimum 68–70 °C), a neutrophile (growth at pH25 °C 4.8–8.0; optimum pH25 °C 6.8) and an obligate organotroph (growth by fermentation of various sugars, peptides and polysaccharides). Major fermentation products were acetate, H2 and CO2; ethanol, lactate and l-alanine were formed in smaller amounts. Thiosulfate stimulated growth and was reduced to hydrogen sulfide. Nitrate, sulfate, sulfite and elemental sulfur were not reduced and did not stimulate growth. Thus, according to the strain's phylogenetic position and phenotypic novelties (lower upper limit of temperature range for growth, the ability to grow on arabinose, the inability to reduce elemental sulfur and the formation of alanine as a minor fermentation product), the novel species Caldanaerobacter uzonensis sp. nov. is proposed, with the type strain K67T (=DSM 18923T =VKM В-2408T).

scholarly journals Nitrate removal by a novel lithoautotrophic nitrate-reducing iron(II)-oxidizing culture enriched from a pyrite-rich limestone aquifer

2021 ◽  
Author(s):  
Natalia Jakus ◽  
Nia Blackwell ◽  
Karsten Osenbrück ◽  
Daniel Straub ◽  
James M. Byrne ◽  
...  
Keyword(s):  
Microbial Community ◽  
Organic Carbon ◽  
Electron Donor ◽  
Nitrate Reduction ◽  
Nitrate Removal ◽  
Electron Donors ◽  
Rrna Gene ◽  
Organic Substrates ◽  
Limestone Aquifer ◽  
Chemolithoautotrophic Bacteria

Nitrate removal in oligotrophic environments is often limited by the availability of suitable organic electron donors. Chemolithoautotrophic bacteria may play a key role in denitrification in aquifers depleted in organic carbon. Under anoxic and circumneutral pH conditions, iron(II) was hypothesized to serve as an electron donor for microbially mediated nitrate reduction by Fe(II)-oxidizing (NRFeOx) microorganisms. However, lithoautotrophic NRFeOx cultures have never been enriched from any aquifer and as such there are no model cultures available to study the physiology and geochemistry of this potentially environmentally relevant process. Using iron(II) as an electron donor, we enriched a lithoautotrophic NRFeOx culture from nitrate-containing groundwater of a pyrite-rich limestone aquifer. In the enriched NRFeOx culture that does not require additional organic co-substrates for growth, within 7-11 days 0.3-0.5 mM of nitrate was reduced and 1.3-2 mM of iron(II) was oxidized leading to a stoichiometric NO 3 - /Fe(II) ratio of 0.2, with N 2 and N 2 O identified as the main nitrate reduction products. Short-range ordered Fe(III) (oxyhydr)oxides were the product of iron(II) oxidation. Microorganisms were observed to be closely associated with formed minerals but only few cells were encrusted, suggesting that most of the bacteria were able to avoid mineral precipitation at their surface. Analysis of the microbial community by long-read 16S rRNA gene sequencing revealed that the culture is dominated by members of the Gallionellaceae family that are known as autotrophic, neutrophilic, microaerophilic iron(II)-oxidizers. In summary, our study suggests that NRFeOx mediated by lithoautotrophic bacteria can lead to nitrate removal in anthropogenically impacted aquifers. Importance Removal of nitrate by microbial denitrification in groundwater is often limited by low concentrations of organic carbon. In these carbon-poor ecosystems, nitrate-reducing bacteria that can use inorganic compounds such as Fe(II) (NRFeOx) as electron donors could play a major role in nitrate removal. However, no lithoautotrophic NRFeOx culture has been successfully isolated or enriched from this type of environment and as such there are no model cultures available to study the rate-limiting factors of this potentially important process. Here we present the physiology and microbial community composition of a novel lithoautotrophic NRFeOx culture enriched from a fractured aquifer in southern Germany. The culture is dominated by a putative Fe(II)-oxidizer affiliated with the Gallionellaceae family and performs nitrate reduction coupled to Fe(II) oxidation leading to N 2 O and N 2 formation without the addition of organic substrates. Our analyses demonstrate that lithoautotrophic NRFeOx can potentially lead to nitrate removal in nitrate-contaminated aquifers.

scholarly journals Magnetospirillum bellicus sp. nov., a Novel Dissimilatory Perchlorate-Reducing Alphaproteobacterium Isolated from a Bioelectrical Reactor

2010 ◽  
Vol 76 (14) ◽  
pp. 4730-4737 ◽  
Author(s):  
J. Cameron Thrash ◽  
Sarir Ahmadi ◽  
Tamas Torok ◽  
John D. Coates
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Electron Donor ◽  
Dna Hybridization ◽  
Carbon Sources ◽  
Rrna Gene ◽  
Separate Species ◽  
Cathodic Chamber ◽  
Magnetospirillum Magnetotacticum ◽  
Reducing Bacteria

ABSTRACT Previously isolated dissimilatory perchlorate-reducing bacteria (DPRB) have been primarily affiliated with the Betaproteobacteria. Enrichments from the cathodic chamber of a bioelectrical reactor (BER) inoculated from creek water in Berkeley, CA, yielded a novel organism most closely related to a previously described strain, WD (99% 16S rRNA gene identity). Strain VDYT has 96% 16S rRNA gene identity to both Magnetospirillum gryphiswaldense and Magnetospirillum magnetotacticum, and along with strain WD, distinguishes a clade of perchlorate-reducing Magnetospirillum species in the Alphaproteobacteria. In spite of the phylogenetic location of VDYT, attempted PCR for the key magnetosome formation genes mamI and mamL was negative. Strain VDYT was motile, non-spore forming, and, in addition to perchlorate, could use oxygen, chlorate, nitrate, nitrite, and nitrous oxide as alternative electron acceptors with acetate as the electron donor. Transient chlorate accumulation occurred during respiration of perchlorate. The organism made use of fermentation end products, such as acetate and ethanol, as carbon sources and electron donors for heterotrophic growth, and in addition, strain VDYT could grow chemolithotrophically with hydrogen serving as the electron donor. VDYT contains a copy of the RuBisCo cbbM gene, which was expressed under autotrophic but not heterotrophic conditions. DNA-DNA hybridization with strain WD confirmed VDYT as a separate species (46.2% identity), and the name Magnetospirillum bellicus sp. nov. (DSM 21662, ATCC BAA-1730) is proposed.

Palaeococcus pacificus sp. nov., an archaeon from deep-sea hydrothermal sediment

2013 ◽  
Vol 63 (Pt_6) ◽  
pp. 2155-2159 ◽  
Author(s):  
Xiang Zeng ◽  
Xiaobo Zhang ◽  
Lijing Jiang ◽  
Karine Alain ◽  
Mohamed Jebbar ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Elemental Sulfur ◽  
Phylogenetic Analyses ◽  
Rrna Gene ◽  
Strictly Anaerobic ◽  
Content Type ◽  
Physiological Properties ◽  
Casamino Acids ◽  
Gene Similarity

A hyperthermophilic, anaerobic, piezophilic archaeon (strain DY20341T) was isolated from a sediment sample collected from an East Pacific Ocean hydrothermal field (1° 37′ S 102° 45′ W) at a depth of 2737 m. The cells were irregular cocci, 0.8–1.5 µm in diameter. Growth was observed between 50 and 90 °C (optimum 80 °C), pH 5.0 and 8.0 (optimum pH 7.0), 1 % and 7 % (w/v) sea salts (Sigma, optimum 3 %), 1 % and 4 % (w/v) NaCl (optimum 3 %) and 0.1 and 80 MPa (optimum 30 MPa). The minimum doubling time was 66 min at 30 MPa and 80 °C. The isolate was an obligate chemoorganoheterotroph, capable of utilizing complex organic compounds and organic acids including yeast extract, peptone, tryptone, casein, starch, Casamino acids, citrate, lactate, acetate, fumarate, propanoate and pyruvate for growth. It was strictly anaerobic and facultatively dependent on elemental sulfur or sulfate as electron acceptors, but did not reduce sulfite, thiosulfate, Fe(III) or nitrate. The presence of elemental sulfur enhanced growth. The G+C content of the genomic DNA was 43.6±1 mol%. 16S rRNA gene sequence analysis revealed that the closest relative of the isolated organism was Palaeococcus ferrophilus DMJT (95.7 % 16S rRNA gene similarity). On the basis of its physiological properties and phylogenetic analyses, the isolate is considered to represent a novel species, for which the name Palaeococcus pacificus sp. nov. is proposed. The type strain is strain DY20341T ( = JCM 17873T = DSM 24777T).

scholarly journals Woeseiales transcriptional response in Arctic fjord surface sediment

2020 ◽  
Author(s):  
Joy Buongiorno ◽  
Katie Sipes ◽  
Kenneth Wasmund ◽  
Alexander Loy ◽  
Karen G. Lloyd
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Marine Sediments ◽  
Sulfur Oxidation ◽  
Mrna Abundance ◽  
Nitrite Reduction ◽  
Gene Analysis ◽  
Rrna Gene ◽  
16S Rrna Gene Analysis ◽  
Arctic Fjord

AbstractDistinct lineages of Gammaproteobacteria clade Woeseiales are globally-distributed in marine sediments, based on metagenomic and 16S rRNA gene analysis. Yet little is known about why they are dominant or their ecological role in Arctic fjord sediments, where glacial retreat is rapidly imposing change. This study combined 16S rRNA gene analysis, metagenome-assembled genomes (MAGs), and genome-resolved metatranscriptomics uncovered the in situ abundance and transcriptional activity of Woeseiales with burial in four shallow sediment sites of Kongsfjorden and Van Keulenfjorden of Svalbard (79°N). We present five novel Woeseiales MAGs and show transcriptional evidence for metabolic plasticity during burial, including sulfur oxidation with reverse dissimilatory sulfite reductase (dsrAB) down to 4 cm depth and nitrite reduction down to 6 cm depth. A single stress protein, spore protein SP21 (hspA), had a tenfold higher mRNA abundance than any other transcript, and was a hundredfold higher on average than other transcripts. At three out of the four sites, SP21 transcript abundance increased with depth, while total mRNA abundance and richness decreased, indicating a shift in investment from metabolism and other cellular processes to build-up of spore protein SP21. The SP21 gene in MAGs was often flanked by genes involved in membrane-associated stress response. The ability of Woeseiales to shift from sulfur oxidation to nitrite reduction with burial into marine sediments with decreasing access to overlying oxic bottom waters, as well as enter into a dormant state dominated by SP21, may account for its ubiquity and high abundance in marine sediments worldwide, including those of the rapidly shifting Arctic.

Sign in / Sign up

Export Citation Format

Share Document