Article
Chemistry, Medicinal
Yujian Wang, Jian Zhang, Yuanyuan Sun, Li Sun
Summary: Crus1, a type of antimicrobial peptide from deep-sea shrimp, effectively kills Gram-positive bacteria by inducing membrane leakage and structure damage in a pH, temperature, and disulfide linkage-dependent manner. Serine substitution of cysteine residues in the WAP domain does not affect bacterial binding capacity but completely abolishes the bactericidal activity of rCrus1.
Article
Environmental Sciences
Elin A. Thomas, Aoife Molloy, Nova B. Hanson, Monika Boehm, Mary Seddon, Julia D. Sigwart
Summary: The study shows that 62% of molluscs endemic to hydrothermal vents are under threat, with some species fully protected while others facing threats from deep-sea mining. The relative threat index highlights greater risks at vent fields in the Indian Ocean, while vent sites within established marine protected areas have a higher proportion of species assessed as Least Concern.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Microbiology
Zhichao Zhou, Emily St. John, Karthik Anantharaman, Anna-Louise Reysenbach
Summary: This study explores the genomic diversity in 42 metagenomes from deep-sea hydrothermal vents and documents their potential implications in biogeochemical cycles. The findings reveal a significant expansion of microbial genomic diversity associated with hydrothermal vent deposits and highlight the metabolic adaptation of taxonomic guilds.
Article
Chemistry, Medicinal
Huaran Zhang, Yingying Chen, Yanqing Li, Yongxiang Song, Junying Ma, Jianhua Ju
Summary: The study on Streptomyces sp. SCSIO ZS0520 revealed new secondary metabolites and conducted bioinformatic analysis to lay foundations for solving remaining biosynthetic issues.
Article
Oceanography
Coral Diaz-Recio Lorenzo, Daisy ter Bruggen, George W. Luther, Amy Gartman, Sabine Gollner
Summary: The study investigated the abundance and diversity of copepods associated with foundation species in different physiochemical environments at the active vent site ABE, finding that species richness and Shannon diversity were significantly higher in the Bathymodiolus habitat with lower temperatures, sulfur concentrations, and higher oxygen levels, driven by a community comprised mostly of habitat generalists.
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS
(2021)
Article
Microbiology
Mustafa Yuecel, Serhat Sevgen, Nadine Le Bris
Summary: The study reveals the presence of different sizes of iron particles in the Mid-Atlantic Ridge hydrothermal system, where the nanoparticulate/colloidal phase changes with sample temperature and the distribution of iron particles of different sizes varies in the plume. The results support previous observations of dissolved iron in MAR vent plumes, suggesting that this recalcitrant iron pool contributes to maintaining high hydrothermal iron fluxes to the deep ocean. Unexpected findings in sample collection could have implications for further research.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Environmental Sciences
Mariana Cruz, Nadine Le Bris, Ana Colaco
Summary: This study revealed the reproductive ecology characteristics of hydrothermal vent species S. mesatlantica, including the behavior of brooding female crabs, gametogenesis, fecundity, and embryonic and larvae development. The results showed that brooding crabs exhibit specific brooding behaviors and may provide oxygen to their embryos.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
J. Marticorena, M. Matabos, E. Ramirez-Llodra, C. Cathalot, A. Laes-Huon, R. Leroux, S. Hourdez, J. -P. Donval, J. Sarrazin
Summary: This study implemented a novel experimental approach to assess the recovery potential of vent communities along the slow-spreading northern Mid-Atlantic Ridge. Within 2 years after inducing a small-scale disturbance, most taxonomic richness had recovered, but there was only partial recovery of faunal densities and a major change in faunal composition. The results suggest a potential role of mobile predators in early-colonisation stages.
MARINE ENVIRONMENTAL RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Anran Wei, Ding Yuan, Bingzhi He, Yujie Xie, Andre E. Vellwock, Jin Sun, Haimin Yao
Summary: By studying the unique layered structure and thermal impulse resistance of snail shells in deep-sea hydrothermal environments, we have uncovered the temperature response and structure-property relationship of bilayer materials, providing guidelines for the development of thermal barriers in engineering.
Article
Biotechnology & Applied Microbiology
Caroline S. Fortunato, David A. Butterfield, Benjamin Larson, Noah Lawrence-Slavas, Christopher K. Algar, Lisa Zeigler Allen, James F. Holden, Giora Proskurowski, Emily Reddington, Lucy C. Stewart, Begum D. Topcuoglu, Joseph J. Vallino, Julie A. Huber
Summary: The study found that autotrophic microbial communities in shipboard and seafloor experiments behaved similarly, but the microbes in shipboard incubations were more stressed. Additionally, metabolic differences were apparent and likely linked to the chemistry of the fluid at the beginning of the experiment.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Microbiology
Stephane L'Haridon, Steven Goulaouic, Emily St John, Stephanie Fouteau, Anna-Louise Reysenbach
Summary: Three hyperthermophilic methanogens, designated strain SG7(T), strain SG1 and strain SLH, were isolated from the deep-sea hydrothermal vent fields along the Eastern Lau Spreading Center. They belong to the genus Methanocaldococcus and are most closely related to Methanocaldococcus bathoardescens. The strains exhibit unique characteristics and are proposed as representatives of a novel species, Methanocaldococcus lauensis sp. nov.
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY
(2023)
Article
Environmental Sciences
Monika Neufeld, Anna Metaxas, John W. Jamieson
Summary: While there is extensive research on the ecological communities at active hydrothermal vents, little is known about the fauna at inactive vents and their vulnerability to disturbance. This study examined the abundance patterns of non-vent megafauna on two segments of the Juan de Fuca Ridge and found differences in community composition between sites. The proximity to active vents also influenced the abundance of some species.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Reyhaneh Roohi, Ragna Hoogenboom, Ronald Van Bommel, Marcel T. J. van der Meer, Furu Mienis, Sabine Gollner
Summary: This study investigates the export and influence of carbon produced by hydrothermal vents on benthic food webs. It reveals that fauna near the venting area primarily rely on chemosynthetic organic carbon, while fauna further away from the vents rely more on photosynthetic organic carbon. Nematodes are the most abundant faunal taxon. These findings have important implications for future spatial management plans in deep-sea mining at hydrothermal vents.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Jing-Chang Luo, Jian Zhang, Li Sun
Summary: In this study, a g-type lysozyme (LysG1) was identified and characterized from shrimp inhabiting a deep-sea hydrothermal vent. The recombinant LysG1 exhibited selective bactericidal activity against Gram-negative bacteria by binding to bacterial cell wall components and inducing cell lysis. Mutation analysis revealed the importance of specific protein helixes in the bacterial binding and killing activities of LysG1. These findings provide insights into the activity and mechanism of g-type lysozyme in crustacean and deep-sea organisms.
Article
Zoology
Chong Chen, Julia D. Sigwart
Summary: Deep-sea hydrothermal vents are home to many unique species adapted to these chemosynthesis-based ecosystems. The exploration of vent fields, including those in the tropical Pacific, is increasing due to deep-sea mining. Molecular evidence has revealed that many vent endemic gastropod lineages consist of sibling species pairs in neighboring oceanic basins. In this study, previously unpublished descriptions of several species and a new genus were presented, which are important for their taxonomic recognition and potential conservation needs in the face of future environmental destruction.
Article
Forestry
Ayako Enta, Mika Hayashi, Maximo Larry Lopez Caceres, Lei Fujiyoshi, Toshiro Yamanaka, Akira Oikawa, Felix Seidel
JOURNAL OF FORESTRY RESEARCH
(2020)
Article
Ecology
Yuji Onishi, Toshiro Yamanaka, Ken-Ichi Ozaki, Rei Nakayama, Sho Shimamura, Rie Itami, Ami Fukushima, Megumi Miyamoto, Yoshihiro Fujiwara
MARINE ECOLOGY PROGRESS SERIES
(2020)
Article
Geography, Physical
Takashi Ninomiya, Shoichi Shimoyama, Yuichiro Miyata, Toshiro Yamanaka, Takashi Shimazu, Sho Taniguchi, Takahiro Aoki, Tamio Nishida, Toshihiro Takahashi
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2020)
Article
Agriculture, Dairy & Animal Science
Diyona Putri, Masanori Yokozawa, Toshiro Yamanaka, Adam L. Cronin
Summary: Invasive ant populations exhibit trait plasticity in behavior and diet, showing differences from native populations. Some invasive populations demonstrate the formation of 'supercolonies'.
Article
Agronomy
Felix Seidel, M. Larry C. Lopez, Eleonora Bonifacio, Hiroko Kurokawa, Toshiro Yamanaka, Luisella Celi
Summary: The present study aimed to assess the phosphorus allocation patterns of four tree species during different phenological stages and its relationship with nitrogen concentrations. It was found that nitrogen in plant tissues correlated well with their phosphorus partitioning, and the increase of soil ammonium concentration positively influenced nitrogen reabsorption efficiency.
Article
Construction & Building Technology
Keisuke Takahashi, Yuichiro Kawabata, Mitsuyasu Iwanami, Mari Kobayashi, Takafumi Kasaya, Toshiro Yamanaka, Shun Nomura, Hiroko Makita
Summary: The results of the first-ever in-situ monitoring of a large mortar specimen at a depth of 3515 m in the Nankai Trough are presented in this study. The study successfully monitored the development of strain and hydraulic pressure in the specimen. However, microstructural damage was observed in the specimen after exposure to the deep sea environment for one year, resulting in a decrease in compressive strength and Young's modulus.
JOURNAL OF ADVANCED CONCRETE TECHNOLOGY
(2022)
Article
Agronomy
Kazushi Murata, Fabian Watermann, O. B. Herve Gonroudobou, Le Thuy Hang, Toshiro Yamanaka, M. Larry C. Lopez
Summary: This study found that the invasion of black locust trees led to a shift in nitrogen sources in the soil, which affected nitrogen assimilation in black pine trees.
Article
Archaeology
Chitoshi Mizota, Koji Oba, Youichirou Hisa, Toshiro Yamanaka, Shinji Yamauchi
Summary: Archives from medieval Japan, China, and Korea reveal a significant demand for native sulphur for gunpowder production and war efforts in East Asia. Excavations in Hakata Bay, northern Kyushu, Japan, unearthed sulphur pebbles dating back to the 11th and 12th century CE, marking the earliest industrial use of native sulphur. The sulphur samples share isotopic signatures with volcanic sulphur from Kyushu's active geothermal areas, suggesting provenance. The presence of opal-CT, cristobalite/tridymite, and tridymite fragments support the association of sulphur pebbles with high-temperature volcanic fumaroles. The long-term preservation of the sulphur pebbles within sediments can be attributed to reduced conditions facilitated by the reduction of marine sulphates in pore-waters. This limits microbial oxidation and suggests that the pebbles were likely spilled during cargo handling and incorporated into sediments drifting along the near-shore of Hakata Bay.
JOURNAL OF ARCHAEOLOGICAL SCIENCE-REPORTS
(2022)
Article
Geosciences, Multidisciplinary
N. Moussa, G. Bayon, V. Dekov, T. Yamanaka, R. Shinjo, T. Toki, B. Le Gall, N. Grassineau, J. A. Langlade, M. O. Awaleh, E. Pelleter
Summary: This study reports on the discovery of unusual hydrothermal mixed carbonate-siliceous chimneys in the Allols area, northwest of Lake Asal. These chimneys, up to 20 m high, were formed sub-aqueously and show evidence of mixing between magmatic and surficial waters. The study suggests that these chimneys were formed during major changes in lake water chemistry, reflecting contributions of mixing fluids and basalt alteration.
JOURNAL OF AFRICAN EARTH SCIENCES
(2023)
Article
Chemistry, Analytical
Keiichi Fujimori, Akira Izutani, Kenta Tsujimoto, Masanari Hirahara, Takayo Moriuchi-Kawakami, Masato Ueda, Takahiko Suzue, Hideshi Kimoto, Kei Okamura
Summary: We developed a new chemiluminescence (CL) method for quantifying sulfide in seawater. A terbium-pipemidic acid complex was used as a CL enhancer. The method had a sensitivity eight times higher than previous methods and a limit of detection of 21 nmol/L sulfide. Interfering conservative ions, such as Br-, were investigated, as well as the effects of salinity, temperature, and interfering chemicals. The method was also validated using sulfite-spiked natural seawater samples.
ANALYTICAL SCIENCES
(2023)
Article
Biology
Yuji Onishi, Toshiro Yamanaka, Keisuke Koba
Summary: This study assessed the contribution of chemosynthetic products by sulfur-oxidizing bacteria to the nutritional resources in the benthic food web of Lake Biwa, the largest freshwater lake in Japan. Results showed that 58%-67% of the total biomass sulfur in the benthic food web came from sulfide-derived sulfur, highlighting the importance of chemosynthetic products in supporting the sulfur nutritional resource in the lake ecosystem.
Proceedings Paper
Engineering, Ocean
Keisuke Takahashi, Mari Kobayashi, Yuichiro Kawabata, Takafumi Kasaya, Mitsuyasu Iwanami, Toshiro Yamanaka, Shun Nomura, Hiroko Makita
Summary: In recent years, there has been an increasing demand for deep-sea utilization in both industries and natural science research, and the main utilization of the deep sea is about to begin. This paper introduces the authors' investigations into the mix designs and construction methods of cementitious materials and structures for this trend. The paper also presents the authors' previous studies on the durability of cementitious materials under deep-sea conditions and in-situ casting tests of cementitious materials on the deep seafloor.
2023 IEEE UNDERWATER TECHNOLOGY, UT
(2023)
Article
Archaeology
Chitoshi Mizota, Phanthasin Khanthavong, Takahiro Hosono, Azusa Okumura, Toshiro Yamanaka, Hirotatsu Murano
Summary: Saltpetre, a major component of gunpowder, played a crucial role in historical political changes. The manufacturing process of saltpetre involved extraction, conversion, concentration, scum removal, and differential crystallization. Stable isotope analysis verified limited isotopic modification during the manufacturing processes and emphasized the importance of stable isotopic fingerprinting for identifying the source of saltpetre in historic gunpowder.
JOURNAL OF ARCHAEOLOGICAL SCIENCE-REPORTS
(2021)
Article
Geology
Jaeguk Jo, Toshiro Yamanaka, Dongbok Shin
Summary: In this study, clay minerals such as smectite incorporating ammonium were extracted to investigate ammonium behavior and nitrogen isotope characteristics. The results showed differences in inorganic nitrogen content between sediment cores, with a transformation of exchangeable ammonium to non-exchangeable ammonium during evolving diagenetic process. The nitrogen isotope variance in clay fraction suggests heat flow from deep magma led to nitrogen isotope fractionation.
ECONOMIC AND ENVIRONMENTAL GEOLOGY
(2021)
Article
Environmental Sciences
Tatsuya Hayashi, Toshiro Yamanaka, Yuki Hikasa, Masahiko Sato, Yoshihiro Kuwahara, Masao Ohno
COMMUNICATIONS EARTH & ENVIRONMENT
(2020)
