Fossil bacterial ecosystem at methane seeps

Burhan, R. Y. Perry; Trendel, Jean M.; Adam, Pierre; Wehrung, Patrick; Albrecht, Pierre; Nissenbaum, Arie

doi:10.1016/s0016-7037(02)00979-1

Cited by 62 publications

(14 citation statements)

References 62 publications

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“…C 31 ββ hopane usually indicates the presence of cyanobacteria (Talbot et al, 2008). C 24 -C 26 tetracyclic terpanes (17,21-secohopanes) have been identified in sediments, petroleums and fossilized bacterial ecosystems; these compounds have been attributed to microbial opening of the ring E of hopanoids during early diagenesis caused by the oxidation of 17( 21)-hopenes followed by reduction to the 17,21-secohopane (Burhan et al, 2002;Trendel et al, 1982). Reports of baccharane-derived triterpenoids in the field of natural products are limited and up to now restricted to terrestrial plants.…”

Section: Stress Response and Defense Mechanismsmentioning

confidence: 99%

Structure and function of Shark Bay microbial communities following tropical cyclone Olwyn: A metatranscriptomic and organic geochemical perspective

et al. 2021

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Shark Bay, Western Australia, is episodically impacted by tropical cyclones. During 2015, the region was hit by a category 3 cyclone, "severe tropical cyclone Olywn," leading to the formation of a black sludge in an intertidal zone harboring microbial mats and microbialites. Upon returning to the impacted site 12 months later, the black sludge deposit was still recognizable between the microbialite columns and mucilaginous cobbles near the shoreline in the impacted area. Metatranscriptomic and organic geochemical analyses were carried out on the cyclone-derived materials and impacted microbial mat communities to unravel the structure, function, and potential preservation of these deposits following a tropical cyclone. It was found that samples derived from the black sludge contained low relative abundances of cyanobacteria but had higher proportions of heterotrophic and anaerobic microorganisms (e.g., methanogens and sulfate-reducing bacteria). Increased metabolic activity by these microorganisms (e.g., sulfate reduction and organic matter degradation) is thought to drive calcium carbonate precipitation and helps in mat preservation. Comparison of the aliphatic biomarker by gas chromatography-mass spectrometry (GC-MS) analyses showed that C 25 highly branched isoprenoid (HBI) alkenes were significantly higher in the cyclone-derived materials attributed to the relocation of subtidal sediments containing HBI-producing diatom communities by the tropical cyclone. Raney nickel desulfurization of the polar fraction extracted from a mucilaginous cobble revealed sulfur-bound hopanoids and a series of benzohopanes. The presence of these compounds could be indicative of microbial matter that has been influenced by the tropical cyclone which may have caused elevated levels of water column anoxia promoting increased sulfurization of the organic matter to occur.

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Section: Stress Response and Defense Mechanismsmentioning

confidence: 99%

Structure and function of Shark Bay microbial communities following tropical cyclone Olwyn: A metatranscriptomic and organic geochemical perspective

et al. 2021

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“…Upon burial native sulfur can be reduced to sulfide, whereas extended periods of exposure to oxic conditions lead to its oxidation to sulfate. Indeed, evidence for large filamentous sulfide-oxidizing bacteria such as Beggiatoa or Thioploca is available for only few examples that represent syngenetic native sulfur formation (Druckman et al, 1994; Burhan et al, 2002). Syngenetic native sulfur deposits are formed at the same time as the strata that host them, whereas epigenetic native sulfur deposits (ENSDs) are emplaced after the formation of the host rocks.…”

Section: Introductionmentioning

confidence: 99%

Formation of Large Native Sulfur Deposits Does Not Require Molecular Oxygen

et al. 2019

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Large native (i.e., elemental) sulfur deposits can be part of caprock assemblages found on top of or in lateral position to salt diapirs and as stratabound mineralization in gypsum and anhydrite lithologies. Native sulfur is formed when hydrocarbons come in contact with sulfate minerals in presence of liquid water. The prevailing model for native sulfur formation in such settings is that sulfide produced by sulfate-reducing bacteria is oxidized to zero-valent sulfur in presence of molecular oxygen (O2). Although possible, such a scenario is problematic because: (1) exposure to oxygen would drastically decrease growth of microbial sulfate-reducing organisms, thereby slowing down sulfide production; (2) on geologic timescales, excess supply with oxygen would convert sulfide into sulfate rather than native sulfur; and (3) to produce large native sulfur deposits, enormous amounts of oxygenated water would need to be brought in close proximity to environments in which ample hydrocarbon supply sustains sulfate reduction. However, sulfur stable isotope data from native sulfur deposits emplaced at a stage after the formation of the host rocks indicate that the sulfur was formed in a setting with little solute exchange with the ambient environment and little supply of dissolved oxygen. We deduce that there must be a process for the formation of native sulfur in absence of an external oxidant for sulfide. We hypothesize that in systems with little solute exchange, sulfate-reducing organisms, possibly in cooperation with other anaerobic microbial partners, drive the formation of native sulfur deposits. In order to cope with sulfide stress, microbes may shift from harmful sulfide production to non-hazardous native sulfur production. We propose four possible mechanisms as a means to form native sulfur: (1) a modified sulfate reduction process that produces sulfur compounds with an intermediate oxidation state, (2) coupling of sulfide oxidation to methanogenesis that utilizes methylated compounds, acetate or carbon dioxide, (3) ammonium oxidation coupled to sulfate reduction, and (4) sulfur comproportionation of sulfate and sulfide. We show these reactions are thermodynamically favorable and especially useful in environments with multiple stressors, such as salt and dissolved sulfide, and provide evidence that microbial species functioning in such environments produce native sulfur. Integrating these insights, we argue that microbes may form large native sulfur deposits in absence of light and external oxidants such as O2, nitrate, and metal oxides. The existence of such a process would not only explain enigmatic occurrences of native sulfur in the geologic record, but also provide an explanation for cryptic sulfur and carbon cycling beneath the seabed.

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“…A high amount of 16α(H)-phyllocladane indicates that the coal-forming plants belonged to the conifer families Taxodiaceae, Podocarpaceae, Cupressaceae, Araucariaceae and Phyllocladaceae, while a high abundance of pimarane suggests Pinaceae, Taxodiaceae and Cupressaceae. [50][51][52][53] Other diterpenoid type constituents of the saturated fraction were α-labdane, β-labdane, isopimaradienes, norisopimarane, pimaradiene, atisene, norpimarane, beyerane, isophyllocladene, isopimarane, fichtelite, 16β(H)-phyllocladane and 16α(H)-kaurane ( Fig. S-2).…”

Section: Molecular Composition Of the Organic Mattermentioning

confidence: 99%

“…57 On the other hand, prominent C 31 αβ(R)-hopane was often reported in low rank coals. 45,52,53 Killops et al 58 suggested that the decarboxylation of 31,32-bishomohopanoic acid, which is generally abundant in peats and soils, 59 Based on the m/z 191 mass chromatogram, compounds with the fernene skeleton, fern-9(11)-ene and fern-8-ene, were also identified ( Fig. S-3c).…”

Section: Molecular Composition Of the Organic Mattermentioning

confidence: 99%

Preliminary organic geochemical study of lignite from the Smederevsko Pomoravlje field (Kostolac basin, Serbia): Reconstruction of geological evolution and potential for rational utilization

Djokovic¹,

Mitrović²,

Životić³

et al. 2015

JSCS

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The study was aimed at determining the origin and geological evolution of lignites from the Smederevsko Pomoravlje field (Kostolac Basin, Serbia). The possibility of a rational utilization of the coal was also considered. For this purpose, numerous organic geochemical analyses were applied to representative lignite samples. The obtained results showed that the coal from the Smederevsko Pomoravlje field is a typical humic coal. The peat-forming vegetation was dominated by gymnosperm plants. The coal-forming plants belonged to the gymnosperm families Taxodiaceae, Cupressaceae, Phyllocladaceae and Pinaceae. Other precursors of organic matter (OM) were microbial biomass, ferns and angiosperms. It was established that peatification occurred in a neutral to slightly acidic, fresh water environment under anoxic to suboxic redox conditions. The maturity of the OM is low, in the phase of intense diagenetic processes. The biomarker compositions and values of the corresponding parameters revealed that the Smederevsko Pomoravlje field, the Drmno field (Kostolac Basin) and the "A" field (Kovin deposit) represent a part of a unique lignite basin. The results of this study suggest possible rational utilization of the Smederevsko Pomoravlje lignites in thermal power plants. This is particularly related to samples from coal seam I. A significant amount of gas could be generated from lignites at higher maturities. Eight samples met the basic assumptions for effective gasification.

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Fossil bacterial ecosystem at methane seeps

Cited by 62 publications

References 62 publications

Structure and function of Shark Bay microbial communities following tropical cyclone Olwyn: A metatranscriptomic and organic geochemical perspective

Structure and function of Shark Bay microbial communities following tropical cyclone Olwyn: A metatranscriptomic and organic geochemical perspective

Formation of Large Native Sulfur Deposits Does Not Require Molecular Oxygen

Preliminary organic geochemical study of lignite from the Smederevsko Pomoravlje field (Kostolac basin, Serbia): Reconstruction of geological evolution and potential for rational utilization

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