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Chao Lian - One of the best experts on this subject based on the ideXlab platform.
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seabed features associated with Cold Seep activity at the formosa ridge south china sea integrated application of high resolution acoustic data and photomosaic images
Deep Sea Research Part I: Oceanographic Research Papers, 2021Co-Authors: Zhendong Luan, Chao Lian, Bing Wang, Xin Zhang, Minxiao Wang, Xiujuan Wang, Jun YanAbstract:Abstract High resolution acoustic data, together with high-definition photomosaic images and video observations of the Formosa Ridge Cold Seep Site were obtained using a remotely operated vehicle (ROV). Seabed features of the Cold Seep site were described in detail and the scales and distribution patterns of these features displayed on the seabed were quantitatively analyzed. The Cold Seep site is characterized by irregular and hummocky topography on the seabed relief map and patches with high to medium backscatter intensities on side-scan sonar (SSS) images. Based on visual data, six kinds of seabed features related to Cold Seep activity were identified: gas flares, dense benthic chemosynthetic communities, mussel beds with low population densities, shells and/or shell debris areas, authigenic carbonate concretions, and reduced sediments. Spatially, these seabed features are distributed in an approximately zoned pattern with gas plumes and benthic communities in the innermost part of Site F and the reduced sediments in the outermost part. Based on the integrated acoustic and visual images and in-situ geochemical data, a conceptual model describing the Cold Seep fluid conduits within the shallow subsurface at Site F at the present is established. Briefly, favorable conduits have developed within the authigenic carbonate mound. The conduits channelize the Cold Seep fluids and result in relatively focused discharge of the Seep fluids at the intersections of the conduits and the seabed, to sustain the dense communities there. Additionally, the authigenic carbonate concretions redirect some of the Cold Seep fluids to Seeps at the periphery of the site, resulting in the reduced sediments. Integrated acoustic and visual investigations combined with in situ measurements are an effective way to quantitatively study the spatial extent of a Cold Seep site and can provide detailed information for further study of the Cold Seep system.
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in situ detection of the fine scale heterogeneity of active Cold Seep environment of the formosa ridge the south china sea
Journal of Marine Systems, 2021Co-Authors: Lei Cao, Chao Lian, Xin Zhang, Minxiao Wang, Huan Zhang, Li Zhou, Hao Chen, Hao Wang, Zhendong LuanAbstract:Abstract The active Cold Seep at Formosa Ridge (Site F) sustains the most flourishing ecosystem on the continental slope of the northern South China Sea. However, the physicochemical environment around the Cold Seep has scarcely been investigated. The knowledge about the variability of the seafloor habitat around the Cold Seep was poor and the key processes within the associated chemosynthetic ecosystem remain unclear. Here, we used an in situ integrated sensors detection approach combined with geochemical measurements to investigate the environmental condition around the chemosynthetic ecosystems fueled by the hydrocarbon Seepage. Methane, hydrogen sulfide, dissolved oxygen and other biogenic elements in the bottom water were detected on a fine scale. The mixed gas composition and carbon isotope value of methane from the vent fluids suggested its origin was predominantly biogenic with slight thermogenic incorporation. Both horizontal and vertical variations in methane and oxygen concentrations were observed, which showed contrasting trends in fields from the center of flourishing communities to the margin of sediments. The concentration of methane decreased from 31,200 ppm at the flourishing center to 381 ppm at the margin on a horizontal gradient. The low concentration of hydrogen sulfide indicated that sulfide could be an energy-limiting factor for chemoautotrophic symbionts. The in situ oxygen levels were variable near the flourishing community but homogeneous at the margins. The results suggested that the availability of oxygen and methane played a substantial role in structuring the Seep communities. Overall, from the flourishing center to the periphery, the chemical gradients drive the spatial distribution of chemosynthetic community at site F. The observations of the fine scale survey highlight the heterogeneity of microenvironments and provide novel information on the environmental dynamics within site F for the first time.
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metal adaptation strategies of deep sea bathymodiolus mussels from a Cold Seep and three hydrothermal vents in the west pacific
Science of The Total Environment, 2020Co-Authors: Li Zhou, Minxiao Wang, Huan Zhang, Lei Cao, Xiaocheng Wang, Zhaoshan Zhong, Hao Chen, Haining Wang, Hao Wang, Chao LianAbstract:Deep-sea Bathymodiolus mussels are ubiquitous in most Cold Seeps and hydrothermal fields, where they have adapted to various toxic environments including high metal exposure. However, there is scarce knowledge of metal accumulation and metal-related biomarkers in B. mussels. Here, we present data for metal concentrations (Ag, Cd, Cr, Cu, Fe, Mn, Pb, and Zn) and metal related biomarkers (superoxide dismutase-SOD, catalase-CAT, glutathione peroxidase-GPX, glutathione-GSH, metallothioneins-MTs, and lipid peroxidation-LPO) in different tissues of B. mussels from four different deep-sea geochemical settings: one Cold Seep and three vent fields in the West Pacific Ocean. Results showed that mussel gills generally exhibited higher metal enrichment than the mantle. Mussels from hydrothermal vents usually had higher metal concentrations (Fe, Cr, Cd, and Pb) than those from Cold Seep, which could be related to their higher contents in fluids or sediments. However, despite quite different metals loads among the geochemical environment settings, Mn, Zn, and Cu concentrations varied over a smaller range across the sampling sites, implying biological regulation by deep-sea mussels for these elements. Several statistically significant correlations were observed between SOD, CAT, GSH, MTs, and metal levels in analyzed tissues. Although the vent ecosystem is harsher than the Cold Seep ecosystem, according to our results their mussels' biomarker levels were not so different. This finding suggests that some adaptive or compensatory mechanisms may occur in chronically polluted deep-sea mussels. Principal component analysis allowed for distinguishing different deep-sea settings, indicating that B. mussels are robust indicators of their living environments. We also compared our results with those reported for coastal mussels. To our best knowledge, this is the first integrated study to report metal accumulation and metal-related biomarkers in the deep-sea B. mussels from the West Pacific.
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marinobacter fonticola sp nov isolated from deep sea Cold Seep sediment
International Journal of Systematic and Evolutionary Microbiology, 2020Co-Authors: Zhendong Luan, Chao LianAbstract:In this study, we report a novel Gram-negative bacterium, designated as strain CS412T, isolated from deep-sea sediment collected in a Cold Seep area of the South China Sea. Growth of strain CS412T occurred at 4–40 °C (optimum, 28 °C), pH 5.0–11.0 (optimum, pH 6.0) and with 0–19 % (w/v) NaCl (optimum, 1–2 %). Phylogenetic analysis based on 16S rRNA gene sequence data indicated that strain CS412T belonged to the genus Marinobacter . The closest phylogenetic neighbours of strain CS412T were Marinobacter pelagius HS225T (96.9 %), Marinobacter szutsaonensis NTU-104T (96.8%), Marinobacter santoriniensis NKSG1T (96.4%) and Marinobacter koreensis dd-M3T (96.3 %). The genomic DNA G+C content of strain CS412T was 58.0 mol%. The principal respiratory quinone was ubiquinone-9 (Q-9). The polar lipids of CS412T contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, aminophospholipidand and four glycolipids. The major fatty acids of CS412T contained cyclo-C19 : 0ω8c, C16 : 0, C18 : 1ω7c and C18 : 1ω7c 11-methyl. The results of phylogenetic, physiological, biochemical and morphological analyses suggested that strain CS412T represents a novel species of the genus Marinobacter , and the name Marinobacter fonticola sp. nov. is proposed with the type species CS412T (=CCTCC AB 2019197T=KCTC 72475T).
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in situ raman quantitative detection of the Cold Seep vents and fluids in the chemosynthetic communities in the south china sea
Geochemistry Geophysics Geosystems, 2018Co-Authors: Xin Zhang, Zhendong Luan, Chao Lian, Bing Wang, Minxiao Wang, Lei Cao, Jun YanAbstract:Based on the previously developed deep-sea hybrid Raman insertion probe for Cold Seeps, the in situ detection of a Cold Seep vent and geochemistry analysis of fluids in chemosynthetic communities were conducted at the Formosa Ridge in the northern South China Sea. Three different methods were used to measure the components of the fluids erupting from the Cold Seep vent. The in situ Raman spectra of the Cold Seep fluids indicated the presence of gaseous CH4, C3H8, and H2S. The results indicate that the gases at this site are of biogenic origin; however, the presence of C3H8 suggests that thermogenic methane should not be excluded. The conclusion is also supported by the results of gas chromatography and stable carbon isotope analysis. More significantly, we found that the concentration of SO42- decreases with increasing depth, while the concentrations of CH4 and S-8 increase in fluids in chemosynthetic communities, but without H2S. This finding indicates that the methane is oxidized by sulfate and that elemental sulfur is formed. This process usually occurs in marine sediments as the anaerobic oxidation of methane. Overall, the findings in this work provide a new insight into the geochemical analysis of Cold Seep fluids and in situ evidence of the oxidation of methane in the chemosynthetic communities near Cold Seeps.
Koki Horikoshi - One of the best experts on this subject based on the ideXlab platform.
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psychromonas kaikoae sp nov a novel piezophilic bacterium from the deepest Cold Seep sediments in the japan trench
International Journal of Systematic and Evolutionary Microbiology, 2002Co-Authors: Yuichi Nogi, Chiaki Kato, Koki HorikoshiAbstract:Two strains of obligately piezophilic bacteria were isolated from sediment collected from the deepest Cold-Seep environment with chemosynthesis-based animal communities within the Japan Trench, at a depth of 7434 m. The isolated strains, JT7301 and JT7304 T , were closely affiliated with members of the genus Psychromonas on the basis of 16S rDNA sequence analysis. Hybridization values for DNA-DNA relatedness between these strains and the Psychromonas antarctica reference strain were significantly lower than that accepted as the phylogenetic definition of a species. The optimal temperature and pressure for growth of the isolates were 10 °C and 50 MPa and they produced both eicosapentaenoic acid (C20:5ω3) and docosahexaenoic acid (C22:6) in the membrane layer. Based on the taxonomic differences observed, the isolated strains appear to represent a novel obligately piezophilic Psychromonas species. The name Psychromonas kaikoae sp. nov. (type strain JT7304 T = JCM 11054 T = ATCC BAA-363 T ) is proposed. This is the first proposed obligately piezophilic species of the genus Psychromonas.
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psychromonas kaikoae sp nov a novel from the deepest piezophilic bacterium Cold Seep sediments in the japan trench
International Journal of Systematic and Evolutionary Microbiology, 2002Co-Authors: Yuichi Nogi, Chiaki Kato, Koki HorikoshiAbstract:Two strains of obligately piezophilic bacteria were isolated from sediment collected from the deepest Cold-Seep environment with chemosynthesis-based animal communities within the Japan Trench, at a depth of 7434 m. The isolated strains, JT7301 and JT7304T, were closely affiliated with members of the genus Psychromonas on the basis of 16S rDNA sequence analysis. Hybridization values for DNA-DNA relatedness between these strains and the Psychromonas antarctica reference strain were significantly lower than that accepted as the phylogenetic definition of a species. The optimal temperature and pressure for growth of the isolates were 10 degrees C and 50 MPa and they produced both eicosapentaenoic acid (C20:5omega3) and docosahexaenoic acid (C22:6) in the membrane layer. Based on the taxonomic differences observed, the isolated strains appear to represent a novel obligately piezophilic Psychromonas species. The name Psychromonas kaikoae sp. nov. (type strain JT7304T = JCM 11054T = ATCC BAA-363T) is proposed. This is the first proposed obligately piezophilic species of the genus Psychromonas.
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Molecular phylogenetic analyses of reverse-transcribed bacterial rRNA obtained from deep-sea Cold Seep sediments.
Environmental microbiology, 2002Co-Authors: Fumio Inagaki, Chiaki Kato, Yuri Sakihama, Akira Inoue, Koki HorikoshiAbstract:A depth profile of naturally occurring bacterial community structures associated with the deep-sea Cold Seep push-core sediment in the Japan Trench at a depth of 5343 m were evaluated using molecular phylogenetic analyses of RNA reverse transcription-PCR (RT-PCR) amplified 16S crDNA fragments. A total of 137 clones of bacterial crDNA (complimentary rDNA) phylotypes (phylogenetic types) obtained at three different depths (2-4, 8-10 and 14-16 cm) were identified in partial crDNA sequencings. crDNA phylotypes from the Cold Seep sediment were dominantly composed of delta- and epsilon-Proteobacteria (36% and 42% respectively). Phylotype analysis of crDNA clone libraries and terminal restriction fragment length polymorphism (T-RFLP) analysis revealed that the majority of bacterial components shifted from delta- Proteobacteria to epsilon-Proteobacteria with increasing depth. Among the delta-proteobacterial crDNA clones, the sequences related to the genus Desulfosarcina were dominant. Almost all sequences of crDNA belonging to epsilon-Proteobacteria were affiliated with the same cluster (epsilon-CSG: epsilon-proteobacterial Cold Seep group), and were closely related with rDNA sequences from deep-sea hydrothermal vent environments.
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microbial diversity in sediments collected from the deepest Cold Seep area the japan trench
Marine Biotechnology, 1999Co-Authors: Chiaki Kato, Koki HorikoshiAbstract:The Japan Trench land slope at a depth of 6,400 m is the deepest Cold-Seep environment with Calyptogena communities. Sediment samples from inside and beside the Calyptogena communities were collected, and the microbial diversity in the sediment samples was studied by molecular phylogenetic techniques. From DNA extracted directly from the sediment samples, 16S rDNAs were amplified by the polymerase chain reaction method. The sequences of the amplified 16S rDNAs selected by restriction fragment length polymorphism analysis were determined and compared with sequences in DNA databases. The results showed that 33 different bacterial 16S rDNA sequences from the two samples analyzed fell into similar phylogenetic categories, the α-, γ-, δ-, and ɛ-subdivisions of Proteobacteria, Cytophaga, and gram-positive bacteria; some of the 16S rDNA sequences were common to both samples. δ- and ɛ-Proteobacteria-related sequences were abundant in both sediments. These sequences are mostly related to sulfate-reducing or sulfur-reducing bacteria and epibionts, respectively. Eight different archaeal 16S rDNA sequences were cloned from the sediments. The majority of the archaeal 16S rDNA sequences clustered in Crenarchaeota and showed high similarities to marine group I archaeal rDNA. A Methanococcoides burtonii–related sequence obtained from the sediment clustered in the Euryarchaeota indicating that M. burtonii–related strains in the area of Calyptogena communities may contribute to production of methane in this environment. From these results, we propose a possible model of sulfur circulation within the microbial community and that of Calyptogena clams in the Cold-Seep environment.
Minxiao Wang - One of the best experts on this subject based on the ideXlab platform.
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seabed features associated with Cold Seep activity at the formosa ridge south china sea integrated application of high resolution acoustic data and photomosaic images
Deep Sea Research Part I: Oceanographic Research Papers, 2021Co-Authors: Zhendong Luan, Chao Lian, Bing Wang, Xin Zhang, Minxiao Wang, Xiujuan Wang, Jun YanAbstract:Abstract High resolution acoustic data, together with high-definition photomosaic images and video observations of the Formosa Ridge Cold Seep Site were obtained using a remotely operated vehicle (ROV). Seabed features of the Cold Seep site were described in detail and the scales and distribution patterns of these features displayed on the seabed were quantitatively analyzed. The Cold Seep site is characterized by irregular and hummocky topography on the seabed relief map and patches with high to medium backscatter intensities on side-scan sonar (SSS) images. Based on visual data, six kinds of seabed features related to Cold Seep activity were identified: gas flares, dense benthic chemosynthetic communities, mussel beds with low population densities, shells and/or shell debris areas, authigenic carbonate concretions, and reduced sediments. Spatially, these seabed features are distributed in an approximately zoned pattern with gas plumes and benthic communities in the innermost part of Site F and the reduced sediments in the outermost part. Based on the integrated acoustic and visual images and in-situ geochemical data, a conceptual model describing the Cold Seep fluid conduits within the shallow subsurface at Site F at the present is established. Briefly, favorable conduits have developed within the authigenic carbonate mound. The conduits channelize the Cold Seep fluids and result in relatively focused discharge of the Seep fluids at the intersections of the conduits and the seabed, to sustain the dense communities there. Additionally, the authigenic carbonate concretions redirect some of the Cold Seep fluids to Seeps at the periphery of the site, resulting in the reduced sediments. Integrated acoustic and visual investigations combined with in situ measurements are an effective way to quantitatively study the spatial extent of a Cold Seep site and can provide detailed information for further study of the Cold Seep system.
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in situ detection of the fine scale heterogeneity of active Cold Seep environment of the formosa ridge the south china sea
Journal of Marine Systems, 2021Co-Authors: Lei Cao, Chao Lian, Xin Zhang, Minxiao Wang, Huan Zhang, Li Zhou, Hao Chen, Hao Wang, Zhendong LuanAbstract:Abstract The active Cold Seep at Formosa Ridge (Site F) sustains the most flourishing ecosystem on the continental slope of the northern South China Sea. However, the physicochemical environment around the Cold Seep has scarcely been investigated. The knowledge about the variability of the seafloor habitat around the Cold Seep was poor and the key processes within the associated chemosynthetic ecosystem remain unclear. Here, we used an in situ integrated sensors detection approach combined with geochemical measurements to investigate the environmental condition around the chemosynthetic ecosystems fueled by the hydrocarbon Seepage. Methane, hydrogen sulfide, dissolved oxygen and other biogenic elements in the bottom water were detected on a fine scale. The mixed gas composition and carbon isotope value of methane from the vent fluids suggested its origin was predominantly biogenic with slight thermogenic incorporation. Both horizontal and vertical variations in methane and oxygen concentrations were observed, which showed contrasting trends in fields from the center of flourishing communities to the margin of sediments. The concentration of methane decreased from 31,200 ppm at the flourishing center to 381 ppm at the margin on a horizontal gradient. The low concentration of hydrogen sulfide indicated that sulfide could be an energy-limiting factor for chemoautotrophic symbionts. The in situ oxygen levels were variable near the flourishing community but homogeneous at the margins. The results suggested that the availability of oxygen and methane played a substantial role in structuring the Seep communities. Overall, from the flourishing center to the periphery, the chemical gradients drive the spatial distribution of chemosynthetic community at site F. The observations of the fine scale survey highlight the heterogeneity of microenvironments and provide novel information on the environmental dynamics within site F for the first time.
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gametogenesis and reproductive traits of the Cold Seep mussel gigantidas platifrons in the south china sea
Journal of Oceanology and Limnology, 2020Co-Authors: Zhaoshan Zhong, Minxiao Wang, Hao Chen, Ping ZhengAbstract:Gigantidas platifrons (Bivalvia, Mytilidae), the dominant species at the Formosa Cold Seep, relies on methanotrophic symbionts dwelling in its gills for nutrition. The reproductive patterns of G. platifrons provide fundamental information for understanding the population recruitment of this species. However, we know very little about important processes in reproduction, such as gametogenesis and symbiotic bacteria transmission. To this end, we described the developmental patterns of the gonads from nine surveys and juvenile length-distribution from one-year larval traps and detected bacteria in gonad from G. platifrons samples. Our results show that G. platifrons is a functionally dioecious species. The reproduction of G. platifrons is discontinuous, with spawning maturity peak around the fourth quarter of the year. The seasonal reproduction of G. platifrons was further supported by the unimodal shell length distribution of the trapped juvenile mussels. Given the small oocyte size (48.99-70.14 μm), which was comparable to that of coastal mussels, we proposed that G. platifrons developed via a free-living, planktotrophic larval stage before settlement. The blooms at the water surface can also supply the development of the planktonic larvae of G. platifrons. Meanwhile, no bacteria were observed in gonads, suggesting a horizontal symbiont transfer mode in this mussel. Collectively, these results provide fundamental biological information for an improved understanding of the early life history of G. platifrons in the Formosa Cold Seep.
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high throughput sequencing reveals a potentially novel sulfurovum species dominating the microbial communities of the seawater sediment interface of a deep sea Cold Seep in south china sea
Microorganisms, 2020Co-Authors: Qinglei Sun, Minxiao Wang, Lei Cao, Jian Zhang, Yuanyuan Sun, Shiqi Liu, Li SunAbstract:In the Formosa Cold Seep of the South China Sea (SCS), large amounts of methane and sulfide hydrogen are released from the subseafloor. In this study, we systematically investigated the microbial communities in the seawater-sediment interface of Formosa Cold Seep using high-throughput sequencing techniques including amplicon sequencing based on next-generation sequencing and Pacbio amplicon sequencing platforms, and metagenomics. We found that Sulfurovum dominated the microbial communities in the sediment-seawater interface, including the seawater close to the Seepage, the surface sediments, and the gills of the dominant animal inhabitant (Shinkaia crosnieri). A nearly complete 16S rRNA gene sequence of the dominant operational taxonomic units (OTUs) was obtained from the Pacbio sequencing platforms and classified as OTU-L1, which belonged to Sulfurovum. This OTU was potentially novel as it shared relatively low similarity percentages (<97%) of the gene sequence with its close phylogenetic species. Further, a draft genome of Sulfurovum was assembled using the binning technique based on metagenomic data. Genome analysis suggested that Sulfurovum sp. in this region may fix carbon by the reductive tricarboxylic acid (rTCA) pathway, obtain energy by oxidizing reduced sulfur through sulfur oxidizing (Sox) pathway, and utilize nitrate as electron acceptors. These results demonstrated that Sulfurovum probably plays an important role in the carbon, sulfur, and nitrogen cycles of the Formosa Cold Seep of the SCS. This study improves our understanding of the diversity, distribution, and function of sulfur-oxidizing bacteria in deep-sea Cold Seep.
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metal adaptation strategies of deep sea bathymodiolus mussels from a Cold Seep and three hydrothermal vents in the west pacific
Science of The Total Environment, 2020Co-Authors: Li Zhou, Minxiao Wang, Huan Zhang, Lei Cao, Xiaocheng Wang, Zhaoshan Zhong, Hao Chen, Haining Wang, Hao Wang, Chao LianAbstract:Deep-sea Bathymodiolus mussels are ubiquitous in most Cold Seeps and hydrothermal fields, where they have adapted to various toxic environments including high metal exposure. However, there is scarce knowledge of metal accumulation and metal-related biomarkers in B. mussels. Here, we present data for metal concentrations (Ag, Cd, Cr, Cu, Fe, Mn, Pb, and Zn) and metal related biomarkers (superoxide dismutase-SOD, catalase-CAT, glutathione peroxidase-GPX, glutathione-GSH, metallothioneins-MTs, and lipid peroxidation-LPO) in different tissues of B. mussels from four different deep-sea geochemical settings: one Cold Seep and three vent fields in the West Pacific Ocean. Results showed that mussel gills generally exhibited higher metal enrichment than the mantle. Mussels from hydrothermal vents usually had higher metal concentrations (Fe, Cr, Cd, and Pb) than those from Cold Seep, which could be related to their higher contents in fluids or sediments. However, despite quite different metals loads among the geochemical environment settings, Mn, Zn, and Cu concentrations varied over a smaller range across the sampling sites, implying biological regulation by deep-sea mussels for these elements. Several statistically significant correlations were observed between SOD, CAT, GSH, MTs, and metal levels in analyzed tissues. Although the vent ecosystem is harsher than the Cold Seep ecosystem, according to our results their mussels' biomarker levels were not so different. This finding suggests that some adaptive or compensatory mechanisms may occur in chronically polluted deep-sea mussels. Principal component analysis allowed for distinguishing different deep-sea settings, indicating that B. mussels are robust indicators of their living environments. We also compared our results with those reported for coastal mussels. To our best knowledge, this is the first integrated study to report metal accumulation and metal-related biomarkers in the deep-sea B. mussels from the West Pacific.
Yong Wang - One of the best experts on this subject based on the ideXlab platform.
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microbial ecology of sulfur cycling near the sulfate methane transition of deep sea Cold Seep sediments
Environmental Microbiology, 2021Co-Authors: Xiyang Dong, Dong Feng, Yingli Zhou, Pengfei Zheng, Yong WangAbstract:Microbial sulfate reduction is largely associated with anaerobic methane oxidation and alkane degradation in sulfate-methane transition zone (SMTZ) of deep-sea Cold Seeps. How the sulfur cycling is mediated by microbes near SMTZ has not been fully understood. In this study, we detected a shallow SMTZ in three of eight sediment cores sampled from two Cold Seep areas in the South China Sea. 110 genomes representing sulfur-oxidizing bacteria (SOB) and sulfur-reducing bacteria (SRB) strains were identified from three SMTZ-bearing cores. In the layers above SMTZ, SOB were mostly constituted by Campylobacterota, Gammaproteobacteria and Alphaproteobacteria that probably depended on nitrogen oxides and/or oxygen for oxidation of sulfide and thiosulfate in near-surface sediment layers. In the layers below the SMTZ, the deltaproteobacterial SRB genomes and metatranscriptomes revealed CO2 fixation by Wood-Ljungdahl pathway, sulfate reduction and nitrogen fixation for syntrophic or fermentative lifestyles. 68% of the MAGs were not adjacent to known species in a phylogenomic tree, indicating a high diversity of bacteria involved in sulfur cycling. With the large number of genomes for SOB and SRB, our study uncovers the microbial populations that potentially mediate sulfur metabolism and associated carbon and nitrogen cycles, which sheds light on complex biogeochemical processes in deep-sea environments. This article is protected by copyright. All rights reserved.
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asgard archaea in the haima Cold Seep spatial distribution and genomic insights
Deep Sea Research Part I: Oceanographic Research Papers, 2021Co-Authors: Zhaoming Gao, Zhanfei Wei, Taoshu Wei, Jiaomei Huang, Jun Tao, Hongbin Wang, Yong WangAbstract:Abstract Asgard archaea, believed to be the ancestor of eukaryotes, constitute a new superphylum prevalent in diverse sediment environments. Their distribution and metabolic potentials are diversified and elusive. In the present study, the distribution and genomic characteristics of Asgard archaea in the Haima Cold Seep of the South China Sea (SCS) were investigated. In total, we obtained 48 high-quality metagenome-assembled genomes (MAGs), which fell into 7 separated lineages affiliated with the phyla Lokiarchaeota, Thorarchaeota, Heimdallarchaeota and Gerdarchaeota. These Asgard archaea were mainly distributed in the Cold Seep but rarely detected in the control marine sediments. We found that Asgard might encode complex CRISPR-Cas systems, which likely protected the archaea against abundant viruses in Cold Seep sediments. Phylogenomic tree indicated the novelty of Cold-Seep Asgard archaea, and highlighted that MAG HM7_B34 was affiliated with the newly proposed Gerdarchaeota phylum. Metabolic reconstruction indicated that Gerdarchaeota in the Haima Cold Seep were obligate anaerobic archaea and might undergo autotrophic lifestyle using the Wood-Ljungdahl pathway. Moreover, Gerdarchaeota might metabolize formaldehyde and likely had the ability to hydrolyze oligosaccharides including chitin. Altogether, our study expands the cognition of Asgard archaea in terms of spatial distribution, biodiversity and carbon cycle in Cold Seep ecosystems.
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metabolic diversification of anaerobic methanotrophic archaea in a deep sea Cold Seep
Marine Life Science & Technology, 2020Co-Authors: Guowei Zhou, Hui Hui Huang, Yong WangAbstract:Anaerobic methanotrophic archaea (ANME) can assimilate methane and govern the greenhouse effect of deep-sea Cold Seeps. In this study, a total of 13 ANME draft genomes representing five ANME types (ANME-1a, ANME-1b, ANME-2a, ANME-2b and ANME-2c), in size between 0.8 and 1.8 Mbp, were obtained from the Jiaolong Cold Seep in the South China Sea. The small metagenome-assembled genomes (MAGs) contained all the essential pathways for methane oxidization and carbon dioxide fixation. All genes related to nitrate and sulfate reduction were absent from the MAGs, indicating their syntrophic dependence on partner organisms. Aside from acetate secretion and sugar storage, propanoate synthesis pathway, as an alternative novel carbon flow, was identified in all the MAGs and transcriptionally active. Regarding type-specific features of the MAGs, the genes encoding archaellum and bacteria-derived chemotaxis were specific to ANME-2, perhaps for fitness under fluctuation of methane and sulfate concentration flux. Our genomic and transcriptomic results strongly suggested that ANME could carry out simple carbon metabolism from C1 assimilation to C3 biosynthesis in the SCS Cold Seep, which casts light on a novel approach for synthetic biology.
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the vertical distribution of prokaryotes in the surface sediment of jiaolong Cold Seep at the northern south china sea
Extremophiles, 2018Co-Authors: Jianwen Qiu, Pei-yuan Qian, Yong WangAbstract:In deep-sea Cold Seeps, microbial communities are shaped by geochemical components in Seepage solutions. In the present study, we report the composition of microbial communities and potential metabolic activities in the surface sediment of Jiaolong Cold Seep at the northern South China Sea. Pyrosequencing of 16S rRNA gene amplicons revealed that a majority of the microbial inhabitants of the surface layers (0–6 cm) were sulfur oxidizer bacteria Sulfurimonas and archaeal methane consumer ANME-1, while sulfate reducer bacteria Seep-SRB1, ANME-1 and ANME-2 dominated the bottom layers (8–14 cm). The potential ecological roles of the microorganisms were further supported by the presence of functional genes for methane oxidation, sulfur oxidation, sulfur reduction and nitrate reduction in the metagenomes. Metagenomic analysis revealed a significant correlation between coverage of 16S rRNA gene of sulfur oxidizer bacteria, functional genes involved in sulfur oxidation and nitrate reduction in different layers, indicating that sulfur oxidizing may be coupled to nitrate reducing at the surface layers of Jiaolong Seeping site. This is probably related to the sulfur oxidizers of Sulfurimonas and Sulfurovum, which may be the capacity of nitrate reduction or associated with unidentified syntrophic nitrate-reducing microbes in the surface of the Cold Seep.
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microbial community changes along the active Seepage site of one Cold Seep in the red sea
Frontiers in Microbiology, 2015Co-Authors: Huiluo Cao, Weipeng Zhang, Yong Wang, Pei-yuan QianAbstract:The active Seepage of the marine Cold Seeps could be a critical process for the exchange of energy between the submerged geosphere and the sea floor environment through organic-rich fluids, potentially even affecting surrounding microbial habitats. However, few studies have investigated the associated microbial community changes. In the present study, 16S rRNA genes were pyrosequenced to decipher changes in the microbial communities from the Thuwal Seepage point in the Red Sea to nearby marine sediments in the brine pool, normal marine sediments and water, and benthic microbial mats. An unexpected number of reads from unclassified groups were detected in these habitats; however, the ecological functions of these groups remain unresolved. Furthermore, ammonia-oxidizing archaeal community structures were investigated using the ammonia monooxygenase subunit A (amoA) gene. Analysis of amoA showed that planktonic marine habitats, including Seeps and marine water, hosted archaeal ammonia oxidizers that differed from those in microbial mats and marine sediments, suggesting modifications of the ammonia oxidizing archaeal (AOA) communities along the environmental gradient from active Seepage sites to peripheral areas. Changes in the microbial community structure of AOA in different habitats (water vs. sediment) potentially correlated with changes in salinity and oxygen concentrations. Overall, the present results revealed for the first time unanticipated novel microbial groups and changes in the ammonia-oxidizing archaea in response to environmental gradients near the active Seepages of a Cold Seep.
Zhendong Luan - One of the best experts on this subject based on the ideXlab platform.
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seabed features associated with Cold Seep activity at the formosa ridge south china sea integrated application of high resolution acoustic data and photomosaic images
Deep Sea Research Part I: Oceanographic Research Papers, 2021Co-Authors: Zhendong Luan, Chao Lian, Bing Wang, Xin Zhang, Minxiao Wang, Xiujuan Wang, Jun YanAbstract:Abstract High resolution acoustic data, together with high-definition photomosaic images and video observations of the Formosa Ridge Cold Seep Site were obtained using a remotely operated vehicle (ROV). Seabed features of the Cold Seep site were described in detail and the scales and distribution patterns of these features displayed on the seabed were quantitatively analyzed. The Cold Seep site is characterized by irregular and hummocky topography on the seabed relief map and patches with high to medium backscatter intensities on side-scan sonar (SSS) images. Based on visual data, six kinds of seabed features related to Cold Seep activity were identified: gas flares, dense benthic chemosynthetic communities, mussel beds with low population densities, shells and/or shell debris areas, authigenic carbonate concretions, and reduced sediments. Spatially, these seabed features are distributed in an approximately zoned pattern with gas plumes and benthic communities in the innermost part of Site F and the reduced sediments in the outermost part. Based on the integrated acoustic and visual images and in-situ geochemical data, a conceptual model describing the Cold Seep fluid conduits within the shallow subsurface at Site F at the present is established. Briefly, favorable conduits have developed within the authigenic carbonate mound. The conduits channelize the Cold Seep fluids and result in relatively focused discharge of the Seep fluids at the intersections of the conduits and the seabed, to sustain the dense communities there. Additionally, the authigenic carbonate concretions redirect some of the Cold Seep fluids to Seeps at the periphery of the site, resulting in the reduced sediments. Integrated acoustic and visual investigations combined with in situ measurements are an effective way to quantitatively study the spatial extent of a Cold Seep site and can provide detailed information for further study of the Cold Seep system.
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in situ detection of the fine scale heterogeneity of active Cold Seep environment of the formosa ridge the south china sea
Journal of Marine Systems, 2021Co-Authors: Lei Cao, Chao Lian, Xin Zhang, Minxiao Wang, Huan Zhang, Li Zhou, Hao Chen, Hao Wang, Zhendong LuanAbstract:Abstract The active Cold Seep at Formosa Ridge (Site F) sustains the most flourishing ecosystem on the continental slope of the northern South China Sea. However, the physicochemical environment around the Cold Seep has scarcely been investigated. The knowledge about the variability of the seafloor habitat around the Cold Seep was poor and the key processes within the associated chemosynthetic ecosystem remain unclear. Here, we used an in situ integrated sensors detection approach combined with geochemical measurements to investigate the environmental condition around the chemosynthetic ecosystems fueled by the hydrocarbon Seepage. Methane, hydrogen sulfide, dissolved oxygen and other biogenic elements in the bottom water were detected on a fine scale. The mixed gas composition and carbon isotope value of methane from the vent fluids suggested its origin was predominantly biogenic with slight thermogenic incorporation. Both horizontal and vertical variations in methane and oxygen concentrations were observed, which showed contrasting trends in fields from the center of flourishing communities to the margin of sediments. The concentration of methane decreased from 31,200 ppm at the flourishing center to 381 ppm at the margin on a horizontal gradient. The low concentration of hydrogen sulfide indicated that sulfide could be an energy-limiting factor for chemoautotrophic symbionts. The in situ oxygen levels were variable near the flourishing community but homogeneous at the margins. The results suggested that the availability of oxygen and methane played a substantial role in structuring the Seep communities. Overall, from the flourishing center to the periphery, the chemical gradients drive the spatial distribution of chemosynthetic community at site F. The observations of the fine scale survey highlight the heterogeneity of microenvironments and provide novel information on the environmental dynamics within site F for the first time.
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the applications of the in situ laser spectroscopy to the deep sea Cold Seep and hydrothermal vent system
Solid Earth Sciences, 2020Co-Authors: Xin Zhang, Zhendong Luan, Boyang Xue, Jun YanAbstract:Abstract Cold Seep and hydrothermal vent system have unique function in mass circulation of the earth, and have been explored by in situ detection technologies in past decades. A brief review on the development and the newest applications of in situ laser spectroscopy for deep sea research is presented here. The laser Raman spectroscopy and laser induced breakdown spectroscopy, with the advantages exactly meeting the requirement of the in situ detection, are emphatically introduced in this paper. The prospect of the in situ laser spectroscopy for the possible application in the deep sea is also discussed in this paper, aiming to provide a reference for the future development of spectroscopy.
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marinobacter fonticola sp nov isolated from deep sea Cold Seep sediment
International Journal of Systematic and Evolutionary Microbiology, 2020Co-Authors: Zhendong Luan, Chao LianAbstract:In this study, we report a novel Gram-negative bacterium, designated as strain CS412T, isolated from deep-sea sediment collected in a Cold Seep area of the South China Sea. Growth of strain CS412T occurred at 4–40 °C (optimum, 28 °C), pH 5.0–11.0 (optimum, pH 6.0) and with 0–19 % (w/v) NaCl (optimum, 1–2 %). Phylogenetic analysis based on 16S rRNA gene sequence data indicated that strain CS412T belonged to the genus Marinobacter . The closest phylogenetic neighbours of strain CS412T were Marinobacter pelagius HS225T (96.9 %), Marinobacter szutsaonensis NTU-104T (96.8%), Marinobacter santoriniensis NKSG1T (96.4%) and Marinobacter koreensis dd-M3T (96.3 %). The genomic DNA G+C content of strain CS412T was 58.0 mol%. The principal respiratory quinone was ubiquinone-9 (Q-9). The polar lipids of CS412T contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, aminophospholipidand and four glycolipids. The major fatty acids of CS412T contained cyclo-C19 : 0ω8c, C16 : 0, C18 : 1ω7c and C18 : 1ω7c 11-methyl. The results of phylogenetic, physiological, biochemical and morphological analyses suggested that strain CS412T represents a novel species of the genus Marinobacter , and the name Marinobacter fonticola sp. nov. is proposed with the type species CS412T (=CCTCC AB 2019197T=KCTC 72475T).
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in situ raman quantitative detection of the Cold Seep vents and fluids in the chemosynthetic communities in the south china sea
Geochemistry Geophysics Geosystems, 2018Co-Authors: Xin Zhang, Zhendong Luan, Chao Lian, Bing Wang, Minxiao Wang, Lei Cao, Jun YanAbstract:Based on the previously developed deep-sea hybrid Raman insertion probe for Cold Seeps, the in situ detection of a Cold Seep vent and geochemistry analysis of fluids in chemosynthetic communities were conducted at the Formosa Ridge in the northern South China Sea. Three different methods were used to measure the components of the fluids erupting from the Cold Seep vent. The in situ Raman spectra of the Cold Seep fluids indicated the presence of gaseous CH4, C3H8, and H2S. The results indicate that the gases at this site are of biogenic origin; however, the presence of C3H8 suggests that thermogenic methane should not be excluded. The conclusion is also supported by the results of gas chromatography and stable carbon isotope analysis. More significantly, we found that the concentration of SO42- decreases with increasing depth, while the concentrations of CH4 and S-8 increase in fluids in chemosynthetic communities, but without H2S. This finding indicates that the methane is oxidized by sulfate and that elemental sulfur is formed. This process usually occurs in marine sediments as the anaerobic oxidation of methane. Overall, the findings in this work provide a new insight into the geochemical analysis of Cold Seep fluids and in situ evidence of the oxidation of methane in the chemosynthetic communities near Cold Seeps.