Cyanorhodopsin-II represents a yellow-absorbing proton-pumping rhodopsin clade within cyanobacteria.

Microbial rhodopsins are prevalent in many cyanobacterial groups as a light-energy-harvesting system in addition to the photosynthetic system. It has been suggested that this dual system allows efficient capture of sunlight energy using complementary ranges of absorption wavelengths. However, the diversity of cyanobacterial rhodopsins, particularly in accumulated metagenomic data, remains underexplored.

sp. nov., a hydrogen- and sulphur-oxidizing mesophilic chemolithoautotroph isolated from a deep-sea hydrothermal vent chimney at the Suiyo Seamount in the Western Pacific Ocean.

A novel mesophilic bacterium, strain SS33, was isolated from a deep-sea hydrothermal vent chimney at Suiyo Seamount, Izu-Bonin Arc, Western Pacific Ocean. The cells of strain SS33 were motile short rods with a single polar flagellum. The growth of strain SS33 was observed at the temperature range between 33 and 55 °C (optimum growth at 45 °C), at the pH range between 5.

The Potential of Artificial Cells Functioning under Deep-Sea Conditions.

Artificial cells with reconstructed cellular functions could serve as practical protocell models for studying the early cellular life on the Earth. Investigating the viability of protocell models in extreme environments where life may have arisen is important for advancing origin-of-life research. Here, we tested the survivability of lipid membrane vesicles in deep-sea environments.

gen. nov. sp. nov. and gen. nov. sp. nov., two novel heterotrophs from brittle star .

Two novel Gram-stain-negative, strictly aerobic, halophilic and non-motile bacterial strains, designated NKW23 and NKW57, were isolated from a brittle star collected from a tidal pool in Wakayama, Japan. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that NKW23 represented a member of the family , with CAU 1123 as its closest relative (94.4% sequence identity).

Oceanic and Sedimentary Microbial Sulfur Cycling Controlled by Local Organic Matter Flux During the Ediacaran Shuram Excursion in the Three Gorges Area, South China.

The increased difference in the sulfur isotopic compositions of sedimentary sulfate (carbonate-associated sulfate: CAS) and sulfide (chromium-reducible sulfur: CRS) during the Ediacaran Shuram excursion is attributed to increased oceanic sulfate concentration in association with the oxidation of the global ocean and atmosphere. However, recent studies on the isotopic composition of pyrites have revealed that CRS in sediments has diverse origins of pyrites. These pyrites are formed either in the water column/shallow sediments, where the system is open with respect to sulfate, or in deep sediments, where the system is closed with respect to sulfate.

-linked protein glycosylation in (formerly DPANN) archaea and their hosts.

Members of the kingdom , previously known as DPANN archaea, are characterized by ultrasmall cell sizes and reduced genomes. They primarily thrive through ectosymbiotic interactions with specific hosts in diverse environments. Recent successful cultivations have emphasized the importance of adhesion to host cells for understanding the ecophysiology of .

Characterization of protein glycosylation in an Asgard archaeon.

Archaeal cells are typically enveloped by glycosylated S-layer proteins. Archaeal protein glycosylation provides valuable insights not only into their adaptation to their niches but also into their evolutionary trajectory. Notably, thermophilic modify proteins with -glycans that include two GlcNAc units at the reducing end, resembling the "core structure" preserved across eukaryotes.

Metatranscriptomics-guided genome-scale metabolic reconstruction reveals the carbon flux and trophic interaction in methanogenic communities.

Background: Despite rapid advances in genomic-resolved metagenomics and remarkable explosion of metagenome-assembled genomes (MAGs), the function of uncultivated anaerobic lineages and their interactions in carbon mineralization remain largely uncertain, which has profound implications in biotechnology and biogeochemistry.

Results: In this study, we combined long-read sequencing and metatranscriptomics-guided metabolic reconstruction to provide a genome-wide perspective of carbon mineralization flow from polymers to methane in an anaerobic bioreactor. Our results showed that incorporating long reads resulted in a substantial improvement in the quality of metagenomic assemblies, enabling the effective recovery of 132 high-quality genomes meeting stringent criteria of minimum information about a metagenome-assembled genome (MIMAG).

gen. nov., sp. nov., an anaerobic, obligately syntrophic archaeon, the first isolate of the lineage 'Asgard' archaea, and proposal of the new archaeal phylum phyl. nov. and kingdom regn. nov.

An anaerobic, mesophilic, syntrophic, archaeon strain MK-D1, was isolated as a pure co-culture with sp. strain MK-MG from deep-sea methane seep sediment. This organism is, to our knowledge, the first cultured representative of 'Asgard' archaea, an archaeal group closely related to eukaryotes.

Ocean circulation contributes to genetic connectivity of limpet populations at deep-sea hydrothermal vents in a back-arc basin.

For endemic benthos inhabiting hydrothermal vent fields, larval recruitment is critical for population maintenance and colonization via migration among separated sites. The vent-endemic limpet, , is abundant at deep-sea hydrothermal vents in the Okinawa Trough, a back-arc basin in the northwestern Pacific; nonetheless, it is endangered due to deep-sea mining. This species is associated with many other vent species and is an important successor in these vent ecosystems.

Accelerated Iron Corrosion by Microbial Consortia Enriched from Slime-like Precipitates from a Corroded Metal Apparatus Deployed in a Deep-sea Hydrothermal System.

Microbiologically influenced corrosion refers to the corrosion of metal materials caused or promoted by microorganisms. Although some novel iron-corrosive microorganisms have been discovered in various manmade and natural freshwater and seawater environments, microbiologically influenced corrosion in the deep sea has not been investigated in detail. In the present study, we collected slime-like precipitates composed of corrosion products and microbial communities from a geochemical reactor set on an artificial hydrothermal vent for 14.

A Marine Group A isolate relies on other growing bacteria for cell wall formation.

Most of Earth's prokaryotes live under energy limitation, yet the full breadth of strategies that enable survival under such conditions remain poorly understood. Here we report the isolation of a bacterial strain, IA91, belonging to the candidate phylum Marine Group A (SAR406 or 'Candidatus Marinimicrobia') that is unable to synthesize the central cell wall compound peptidoglycan itself. Using cultivation experiments and microscopy, we show that IA91 growth and cell shape depend on other bacteria, deriving peptidoglycan, energy and carbon from exogenous muropeptide cell wall fragments released from growing bacteria.

Development of an internal two-stage upflow anaerobic reactor integrating biostimulation strategies to enhance the degradation of aromatic compounds in wastewater from purified terephthalic acid and dimethyl terephthalate manufacturing processes.

In this study, we aimed to establish high-rate biological treatment of purified terephthalic acid (PTA) and dimethyl terephthalate (DMT) wastewater that minimizes the inhibitory effects of high concentration benzoate and acetate. To achieve this, we developed a novel bioreactor system and biostimulation strategy. An internal two-stage upflow anaerobic (ITUA) reactor was operated with (i) a packed bed containing green tuff medium underlying (ii) a compartment seeded with anaerobic granular sludge.

Protocol for in vitro phospholipid synthesis combining fatty acid synthesis and cell-free gene expression.

Phospholipids are important biomolecules for the study of lipidomics, signal transduction, biodiesel, and synthetic biology; however, it is difficult to synthesize and analyze phospholipids in a defined in vitro condition. Here, we present a protocol for in vitro production and quantification of phospholipids. We describe steps for preparing a cell-free system consisting of fatty acid synthesis and a gene expression system that synthesizes acyltransferases on liposomes.

Variation in the relationship between odd isotopes of tin in mass-independent fractionation induced by the magnetic isotope effect.

Experimental results are presented showing the variation in the relationship between odd isotopes of tin (Sn) in mass-independent fractionation caused by the magnetic isotope effect (MIE), which has previously only been observed for mercury. These results are consistent with the trend predicted from the difference between the magnitudes of nuclear magnetic moments of odd isotopes with a nuclear spin. However, the correlation between odd isotopes in fractionation induced by the MIE for the reaction system used in this study (solvent extraction using a crown ether) was different from that reported for the photochemical reaction of methyltin.

Rapid Freezing and Cryo-SEM-EDS Imaging of Foraminifera (Unicellular Eukaryotes) Using a Conductive Viscous Cryogenic Glue.

Spatial distribution of water-soluble molecules and ions in living organisms is still challenging to assess. Energy-dispersive X-ray spectroscopy (EDS) via cryogenic scanning electron microscopy (cryo-SEM) is one of the promising methods to study them without loss of dissolved contents. High-resolution cryo-SEM-EDS has challenges in sample preparation, including cross-section exposure and sample drift/charging due to insulative surrounding water.

sp. nov., a moderately thermophilic methanotroph of the family isolated from a deep-sea hydrothermal field.

A novel aerobic methanotrophic bacterium, designated as strain IN45, was isolated from colonisation systems deployed at the Iheya North deep-sea hydrothermal field in the mid-Okinawa Trough. IN45 was a moderately thermophilic obligate methanotroph that grew only on methane or methanol at temperatures between 25 and 56 °C (optimum 45-50 °C). It was an oval-shaped, Gram-reaction-negative, motile bacterium with a single polar flagellum and an intracytoplasmic membrane system.