Enumeration of viruses and prokaryotes in deep-sea sediments and cold seeps of the Gulf of Mexico

The animal communities associated with the deep-sea reducing environment have been studied for almost 30 years, but until now only a single species of ophiuroid, Ophioctenella acies, has been found at both hydrothermal vents and methane cold seeps. Since the faunal overlap between vent and seep communities is small and many endemic species have been found among other taxa (e.g. Mollusca, Crustacea), additional species of ophiuroids were expected at previously unstudied sites. Chemical compositions at reducing sites differ greatly from the nearby bathyal environment. Generally, species adapted to chemosynthetic environments are not found in non-chemosynthetic habitats, but occasional visitors of other bathyal species to vent and seep sites have been recorded among many taxa except ophiuroids. This paper presents an analysis of the ophiuroid fauna found at hydrothermal vents and non-reducing nearby sites on the Mid-Atlantic Ridge and on methane cold seeps in the Gulf of Mexico, at Blake Ridge off South Carolina and south of Barbados. In addition to O. acies, four species were found at vents, Ophiactis tyleri sp. nov., Ophiocten centobi, Ophiomitra spinea and Ophiotreta valenciennesi rufescens. While Ophioctenella acies appears to be restricted to chemosynthetic areas, the other four species were also found in other bathyal habitats. They also occur in low numbers (mostly single individuals), whereas species adapted to hydrothermal areas typically occur in large numbers. Ophioscolex tripapillatus sp. nov. and Ophiophyllum atlanticum sp. nov. are described from nearby non-chemosynthetic sites. In a cold seep south of Barbados, three species of ophiuroids were found, including Ophioctenella acies, Amphiura sp., Ophiacantha longispina sp. nov. and Ophioplinthaca chelys. From the cold seeps at Blake Ridge and the Gulf of Mexico, Ophienigma spinilimbatum gen. et sp. nov. is described, likely restricted to the reducing environment. Ophiotreta valenciennesi rufescens occurred abundantly among Lophelia corals in the Gulf of Mexico seeps, which is the first record of this species from the West Atlantic. Habitat descriptions complement the taxonomic considerations, and the distribution of the animals in reducing environments is discussed.

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Deep sea sediments associated with cold seeps are a subsurface reservoir of viral diversity

10.1101/2020.09.08.284018 ◽

2020 ◽

Author(s):

Zexin Li ◽

Donald Pan ◽

Guangshan Wei ◽

Weiling Pi ◽

Jiang-Hai Wang ◽

...

Keyword(s):

Microbial Communities ◽

Deep Sea ◽

Cold Seep ◽

Hydrocarbon Biodegradation ◽

Viral Diversity ◽

Cold Seeps ◽

Host Interaction ◽

Deep Sea Sediments ◽

Subsurface Reservoir ◽

Network Comparisons

AbstractIn marine ecosystems, viruses exert control on the composition and metabolism of microbial communities, thus influencing overall biogeochemical cycling. Deep sea sediments associated with cold seeps are known to host taxonomically diverse microbial communities, but little is known about viruses infecting these microorganisms. Here, we probed metagenomes from seven geographically diverse cold seeps across global oceans, to assess viral diversity, virus-host interaction, and virus-encoded auxiliary metabolic genes (AMGs). Gene-sharing network comparisons with viruses inhabiting other ecosystems reveal that cold seep sediments harbour considerable unexplored viral diversity. Most cold seep viruses display high degrees of endemism with seep fluid flux being one of the main drivers of viral community composition. In silico predictions linked 14.2% of the viruses to microbial host populations, with many belonging to poorly understood candidate bacterial and archaeal phyla. Lysis was predicted to be a predominant viral lifestyle based on lineage-specific virus/host abundance ratios. Metabolic predictions of prokaryotic host genomes and viral AMGs suggest that viruses influence microbial hydrocarbon biodegradation at cold seeps, as well as other carbon, sulfur and nitrogen cycling via virus-induced mortality and/or metabolic augmentation. Overall, these findings reveal the global diversity and biogeography of cold seep viruses and indicate how viruses may manipulate seep microbial ecology and biogeochemistry.

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Rhythms in Deep-Sea Sediments from Gulf of Mexico and Caribbean: ABSTRACT

AAPG Bulletin ◽

10.1306/819a3eb4-16c5-11d7-8645000102c1865d ◽

1972 ◽

Vol 56 ◽

Author(s):

A. H. Bouma

Keyword(s):

Gulf Of Mexico ◽

Deep Sea ◽

Deep Sea Sediments

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Records of plutonium isotopes in marine sediments from the southern Gulf of Mexico

10.21203/rs.3.rs-914393/v1 ◽

2021 ◽

Author(s):

Jose A. Corcho Alvarado ◽

Misael Diaz-Asenciuo ◽

Stefan Röllin ◽

Juan Carlos Herguera

Keyword(s):

Gulf Of Mexico ◽

Continental Shelf ◽

Water Column ◽

Deep Sea ◽

Sediment Cores ◽

Global Fallout ◽

Tropical Region ◽

Deep Sea Sediments ◽

Pu Isotopes ◽

Upper Slope

Abstract Here we report on new data on plutonium (Pu) isotopes to elucidate activity concentrations, inventories, sources and their transport from the ocean surface to the sea floor from a collection of deep-sea sediment cores (depths ranging from 257 to 3739 m) in the Gulf of Mexico (GoM). Sediment cores collected from the continental shelf and upper slope region of the GoM consistently showed 240Pu/239Pu ratios of 0.15 to 0.26 and Pu-inventories ranging from 15 to 35 Bq m− 2. Inventories and ratios are consistent with global fallout Pu for this tropical region. In the continental shelf and upper slope regions, higher particle concentrations close to the margins favor significant scavenging and removal of Pu from the water column; in contrast with the deep-sea cores that show low 240Pu/239Pu ratios (0.07–0.13) and a much lower Pu inventory (< 7 Bq m-2) implying a small fraction of the expected global fallout inventory has reached into the lower slopes and abyssal plain of the GoM. Low values and a progressive decrease of 240Pu/239Pu ratios and Pu inventories with increasing water depth have been previously reported for the GoM. The low Pu ratios indicate that Nevada tests fallout was an important source of Pu to deep-sea sediments, and that this source was likely more efficiently removed from the water column than global fallout Pu. Analysis of Pu isotopes in two sediment traps from the upper slope regions show 240Pu/239Pu ratios comparable to the ones observed in the global fallout. These results indicate that global fallout Pu is currently the main source of Pu in water column particles. Therefore, a significant fraction of global fallout Pu must still be present; either in a dissolved phase, or as biologically recycled material in the water column, or scavenged on the shelf and shelf break. Our results bring to light important questions on the application of Pu isotopes to establish sediment chronologies, since these radionuclides are shown to be tracers of bioturbation rather than accumulation processes in deep-sea sediments of the GoM, similar to previously reported results from excess 210Pb.

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Molecular Legacy of the 1979 Ixtoc 1 Oil Spill in Deep-Sea Sediments of the Southern Gulf of Mexico

Deep Oil Spills ◽

10.1007/978-3-030-11605-7_19 ◽

2019 ◽

pp. 312-327 ◽

Cited By ~ 1

Author(s):

Sara A. Lincoln ◽

Jagoš R. Radović ◽

Adolfo Gracia ◽

Aprami Jaggi ◽

Thomas B. P. Oldenburg ◽

...

Keyword(s):

Gulf Of Mexico ◽

Oil Spill ◽

Deep Sea ◽

Deep Sea Sediments ◽

Southern Gulf Of Mexico

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Paleomagnetic excursion recorded in latest Pleistocene deep-sea sediments, Gulf of Mexico

Earth and Planetary Science Letters ◽

10.1016/0012-821x(73)90127-1 ◽

1973 ◽

Vol 19 (2) ◽

pp. 267-274 ◽

Cited By ~ 46

Author(s):

H.C. Clark ◽

J.P. Kennett

Keyword(s):

Gulf Of Mexico ◽

Deep Sea ◽

Deep Sea Sediments

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Extra-Heavy Crude Oil Degradation by Alternaria sp. Isolated from Deep-Sea Sediments of the Gulf of Mexico

Applied Sciences ◽

10.3390/app11136090 ◽

2021 ◽

Vol 11 (13) ◽

pp. 6090

Author(s):

Lucia Romero-Hernández ◽

Patricia Velez ◽

Itandehui Betanzo-Gutiérrez ◽

María Dolores Camacho-López ◽

Rafael Vázquez-Duhalt ◽

...

Keyword(s):

Carbon Source ◽

Gulf Of Mexico ◽

Crude Oil ◽

Deep Sea ◽

Sole Carbon Source ◽

The United States ◽

Heavy Crude Oil ◽

Deep Sea Sediments ◽

Alternaria Sp ◽

Heavy Crude

The Gulf of Mexico (GoM) is an important source of oil for the United States and Mexico. There has been growing interest, particularly after the Deepwater Horizon oil spill, in characterizing the fungal diversity of the GoM and identifying isolates for use in the bioremediation of petroleum in the event of another spill. Most studies have focused on light crude oil bioremediation processes, while heavy crude oil (HCO) and extra-heavy crude oil (EHCO) have been largely ignored. In this work, we evaluated the ability of fungal isolates obtained from deep-sea sediments of the Mexican economic exclusive zone (EEZ) of the GoM to degrade HCO (16–20° API) and EHCO (7–10° API). Alternaria sp., Penicillium spp., and Stemphylium sp. grew with HCO as the sole carbon source. Remarkably, Alternaria sp. was the only isolate able to grow with EHCO as the sole carbon source, degrading up to 25.6% of the total EHCO and 91.3% of the aromatic fraction, as demonstrated by gas chromatography analysis of the saturate, aromatic, and polar fractions. These findings proved to be significant, identifying Alternaria sp. as one of the few fungi reported so far capable of degrading untreated EHCO and as a suitable candidate for bioremediation of EHCO in future studies.

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