A hunting ground for predatory bacteria at the Zhenbei seamount in the South China Sea.

Seamounts are critical marine biodiversity hot spots, while the metabolic activity of their microbial community remains largely unknown. In this study, we investigated the diversity and activity of free-living and particle-attached microorganisms in the surface, middle, and bottom layers of seawater at the Zhenbei seamount in the South China Sea using omics approaches, including 16S ribosomal RNA (rRNA)/16S rDNA ratio analysis. Over 20 phyla were detected, with , , , , , and being predominant.

Novel isolates of hydrogen-oxidizing chemolithoautotrophic provide insight to the functions and adaptation mechanisms of Campylobacteria in shallow-water hydrothermal vents.

Enhancing the availability of representative isolates from hydrothermal vents (HTVs) is imperative for comprehending the microbial processes that propel the vent ecosystem. In recent years, Campylobacteria have emerged as the predominant and ubiquitous taxon across both shallow and deep-sea vent systems. Nevertheless, only a few isolates have been cultured, primarily originating from deep-sea HTVs.

Community Composition and Functional Characterization of Microorganisms in Surface Sediment of the New Britain Trench.

The deep-sea harbors abundant prokaryotic biomass is a major site of organic carbon remineralization and long-term carbon burial in the ocean. Deep-sea trenches are the deepest part of the ocean, and their special geological and morphological features promoting the accumulation of organic matter and active organic carbon turnover. Despite the expanding reports about the organic matter inputs, limited information is known regarding microbial processes in deep-sea trenches.

Determining the abundance, composition and spatial distribution of organohalogens in marine sediments using combustion-ion chromatography.

Understanding the distribution of halogenated organic compounds (HOCs) in marine sediments is essential for understanding the marine carbon and halogen cycling, and also important for assessing the ecosystem health. In this study, a method based on combustion-ion chromatography was developed for determination of the composition and abundance of HOCs in marine sediments. The method showed high accuracy, precision and reproducibility in determining the content of adsorbable organic halogens (AOX), including fluorine, chlorine and bromine (AOF, AOCl, AOBr) and the corresponding insoluble organic halogens (IOF, IOCl, IOBr, IOX), as well as total organic halogen contents (TOX).

Tracing Organophosphate Ester Pollutants in Hadal Trenches─Distribution, Possible Origins, and Transport Mechanisms.

Unraveling the mysterious pathways of pollutants to the deepest oceanic realms holds critical importance for assessing the integrity of remote marine ecosystems. This study tracks the transport of pollutants into the depths of the oceans, a key step in protecting the sanctity of these least explored ecosystems. By analyzing hadal trench samples from the Mariana, Mussau, and New Britain trenches, we found the widespread distribution of organophosphate ester (OPE) flame retardants but a complex transport pattern for the OPE in these regions.

Metagenomic characterization of a novel non-ammonia-oxidizing Thaumarchaeota from hadal sediment.

Background: The hadal sediment, found at an ocean depth of more than 6000 m, is geographically isolated and under extremely high hydrostatic pressure, resulting in a unique ecosystem. Thaumarchaeota are ubiquitous marine microorganisms predominantly present in hadal environments. While there have been several studies on Thaumarchaeota there, most of them have primarily focused on ammonia-oxidizing archaea (AOA).

Biogeographic distribution, ecotype partitioning and controlling factors of Chloroflexi in the sediments of six hadal trenches of the Pacific Ocean.

The hadal trenches are "hot spots" for mineralization of organic matter in the deep ocean. Chloroflexi are one of the most dominant and active taxa in trench sediments, serving as important drivers of carbon cycles in hadal trenches. However, current understanding on hadal Chloroflexi is largely restricted to individual trench.

A symbiotic bacterium of Antarctic fish reveals environmental adaptability mechanisms and biosynthetic potential towards antibacterial and cytotoxic activities.

Antarctic microbes are important agents for evolutionary adaptation and natural resource of bioactive compounds, harboring the particular metabolic pathways to biosynthesize natural products. However, not much is known on symbiotic microbiomes of fish in the Antarctic zone. In the present study, the culture method and whole-genome sequencing were performed.

Metagenomic insights into the functions of microbial communities in sulfur-rich sediment of a shallow-water hydrothermal vent off Kueishan Island.

Hydrothermal vent (HTV) systems are important habitats for understanding the biological processes of extremophiles on Earth and their relative contributions to material and energy cycles in the ocean. Current understanding on hydrothermal systems have been primarily focused on deep-sea HTVs, and little is known about the functions and metabolisms of microorganisms in shallow-water HTVs (SW-HTVs), which are distinguished from deep-sea HTVs by a depth limit of 200 m. In this study, we analyzed metagenomes of sulfur-rich sediment samples collected from a SW-HTV of Kueishan Island, located in a marginal sea of the western Pacific Ocean.

Complete genome sequence of a multiple-stress-tolerant bacterium NBT06E8 isolated from a deep-sea sediment sample of the New Britain Trench.

Unlabelled: NBT06E8 is a Gram-stain-negative, moderately halophilic, piezotolerant, HO and heavy metal-resistant bacterium, isolated from a deep-sea sediment sample collected from the New Britain Trench at depth of 8900 m. Growth of the strain was observed at 4-45 °C (optimum 30 °C), at pH 5-11 (optimum 8-9) and in 0.5-21% (w/v) NaCl (optimum 3-7%).

Microbial communities and biosynthetic pathways for the production of sulfated polysaccharides in the activated sludge system.

Sulfated polysaccharides (SP) are widely used as industrial additives and pharmaceutical intermediates. As SP can only be extracted from sea algae, making them scarce raw materials. Recently, SP have been detected and extracted from the waste activated sludge of a saline secondary wastewater treatment plant, suggesting that there are alternative primary producers and synthesis pathways of the SP within the biological activated sludge.

Novel Chloroflexi genomes from the deepest ocean reveal metabolic strategies for the adaptation to deep-sea habitats.

Background: The deep sea harbors the majority of the microbial biomass in the ocean and is a key site for organic matter (OM) remineralization and storage in the biosphere. Microbial metabolism in the deep ocean is greatly controlled by the generally depleted but periodically fluctuating supply of OM. Currently, little is known about metabolic potentials of dominant deep-sea microbes to cope with the variable OM inputs, especially for those living in the hadal trenches-the deepest part of the ocean.

Microbial Community Structure and Ecological Networks during Simulation of Diatom Sinking.

Microbial-mediated utilization of particulate organic matter (POM) during its downward transport from the surface to the deep ocean constitutes a critical component of the global ocean carbon cycle. However, it remains unclear as to how high hydrostatic pressure (HHP) and low temperature (LT) with the sinking particles affects community structure and network interactions of the particle-attached microorganisms (PAM) and those free-living microorganisms (FLM) in the surrounding water. In this study, we investigated microbial succession and network interactions in experiments simulating POM sinking in the ocean.

Evidence for Long-Term Anthropogenic Pollution: The Hadal Trench as a Depository and Indicator for Dissemination of Antibiotic Resistance Genes.

Knowledge of the distribution and dissemination of antibiotic resistance genes (ARGs) is essential for understanding anthropogenic impacts on natural ecosystems. The transportation of ARGs via aquatic environments is significant and has received great attention, but whether there has been anthropogenic ARG pollution to the hadal ocean ecosystem has not been well explored. For investigating ecological health concerns, we profiled the ARG occurrence in sediments of the Mariana Trench (MT) (10 890 m), the deepest region of the ocean.

Community structure and activity potentials of archaeal communities in hadal sediments of the Mariana and Mussau trenches.

Unlabelled: Hadal trenches are the least explored marine habitat on earth. Archaea has been shown to be the dominant group in trench sediments. However, the activity potentials and detailed diversity of these communities as well as their inter-trench variations are still not known.

Population structure, activity potential and ecotype partitioning of Pseudoalteromonas along the vertical water column of the New Britain Trench.

Microbial degradation of organic matter along the vertical profile of the water column is a major process driving the carbon cycle in the ocean. Pseudoalteromonas has been identified as a dominant genus in pelagic marine environments worldwide, playing important roles in the remineralization of organic carbon. However, the current understanding of Pseudoalteromonas was mainly based on shallow water populations or cultivated species.

Complete genome sequence of a piezophilic bacterium Salinimonas sediminis N102, isolated from deep-sea sediment of the New Britain Trench.

Salinimonas sediminis N102 is a cold-adapted, slightly halophilic piezophile isolated from deep-sea sediment (4700 m) of the New Britain Trench. In this study, we report the complete genome sequence of S. sediminis N102, which is comprised of 4,440,293 base pairs with a mean G + C content of 48.

Bulk and Active Sediment Prokaryotic Communities in the Mariana and Mussau Trenches.

Surprisingly high rates of microbial respiration have recently been reported in hadal trench sediment, yet the potentially active microorganisms and specific microbe-microbe relationships in trench sediment are largely unknown. We investigated the bulk and active prokaryotic communities and co-occurrence interactions of different lineages in vertically sectioned sediment cores taken from the deepest points of the Mariana and Mussau Trenches. Analysis on species novelty revealed for the first time the high rate of novel lineages in the microbial communities of the hadal trenches.

sp. nov., a novel piezophile isolated from hadopelagic water of the Mariana Trench and reclassification of as a later heterotypic synonym of .

A novel marine Gram-stain-negative, non-motile, aerobic and rod-shaped bacterium, designated as strain MT-229, was isolated from the deep seawater in the Mariana Trench and characterized phylogenetically and phenotypically. Bacterial optimal growth occurred at 30 °C (ranging 10-40 °C), pH 6 (ranging 3-11) and with 11 % (w/v) NaCl (ranging 0-17 %). Strain MT-229 was a piezophile, growing optimally at 20 MPa (range 0.

sp. nov., a multiple-stress-tolerant bacterium isolated from a deep-sea sediment sample of the New Britain Trench.

A piezotolerant, HO-tolerant, heavy-metal-tolerant, slightly halophilic bacterium (strain NBT06E8) was isolated from a deep-sea sediment sample collected from the New Britain Trench at depth of 8900 m. The strain was aerobic, motile, Gram-stain-negative, rod-shaped, oxidase-positive and catalase-positive. Growth of the strain was observed at 4-45 °C (optimum, 30 °C), at pH 5-11 (optimum, pH 8-9) and in 0.

Physiological and genomic features of Paraoceanicella profunda gen. nov., sp. nov., a novel piezophile isolated from deep seawater of the Mariana Trench.

A novel piezophilic alphaproteobacterium, strain D4M1 , was isolated from deep seawater of the Mariana Trench. 16S rRNA gene analysis showed that strain D4M1 was most closely related to Oceanicella actignis PRQ-67 (94.2%), Oceanibium sediminis O448 (94.

gen. nov., sp. nov., a piezotolerant bacterium isolated from a deep-sea sediment sample of the New Britain Trench.

A novel alphaproteobacterium, strain WS11, was isolated from a deep-sea sediment sample collected from the New Britain Trench. The full-length 16S rRNA gene of strain WS11 had the highest sequence similarity of 97.6 % to JC85, followed by DSM 7292 (96.