A5101428123- Microbial Community Ecology and Physiology
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
- Underwater Vehicles and Communication Systems
- Genomics and Phylogenetic Studies
- Coral and Marine Ecosystems Studies
- Underwater Acoustics Research
- Legionella and Acanthamoeba research
- Marine and coastal plant biology
- Marine and coastal ecosystems
- Marine and fisheries research
- Oceanographic and Atmospheric Processes
- Isotope Analysis in Ecology
- Marine Bivalve and Aquaculture Studies
- Image Processing and 3D Reconstruction
- Advanced Optical Network Technologies
- Geology and Paleoclimatology Research
- Network Traffic and Congestion Control
- Metaheuristic Optimization Algorithms Research
- Vibrio bacteria research studies
- Environmental DNA in Biodiversity Studies
- Bacteriophages and microbial interactions
- Water Quality Monitoring Technologies
- Marine animal studies overview
- Identification and Quantification in Food
Japan Agency for Marine-Earth Science and Technology
2015-2024
Aichi Shukutoku University
2024
Hiroshima University
2017-2019
Nihon University
2018
Naval Hospital Yokosuka Japan
2018
Mitsubishi Heavy Industries (Germany)
2015-2016
National Institute for Environmental Studies
2016
Biogéosciences
2014
General Oceanics (United States)
2013
The University of Tokyo
2009
Based on the partial nucleotide sequence analysis of 16S ribosomal ribonucleic acid (rRNA), presence unique sphingoglycolipids in cellular lipid, and major type ubiquinone (Q10), we propose Sphingomonas gen. nov. with species paucimobilis (Holmes et al, 1977) comb. From homology values deoxyribonucleic acid-deoxyribonucleic hybridization phenotypic characteristics, three new species, parapaucimobilis, yanoikuyae, adhaesiva, one combination, capsulata, are described. S. parapaucimobilis JCM...
Despite rapidly growing interest in deep-sea mineral exploitation, environmental research and management have focused on impacts to seafloor environments, paying little attention pelagic ecosystems. Nonetheless, indicates that mining will generate sediment plumes noise at the seabed water column may extensive ecological effects deep midwaters (1), which can extend from an approximate depth of 200 meters 5 kilometers. Deep midwater ecosystems represent more than 90% biosphere (2), contain...
There is increasing interest in mining minerals on the seabed, including seafloor massive sulfide deposits that form at hydrothermal vents. The International Seabed Authority currently drafting a Mining Code, environmental regulations, for polymetallic sulfides and other mineral exploitation seabed area beyond national jurisdictions. This paper summarizes 1) ecological vulnerability of active vent ecosystems aspects this remain subject to conjecture, 2) evidence limited resource opportunity...
Phylogenetic positions of psychrophilic bacteria isolated from the Japan Trench were determined by sequencing analysis PCR-amplified bacterial small subunit (16S) rRNA genes. Between surface and deep-sea psychrophiles, distinct clearly differed within gamma-Proteobacteria. In phylogenetic using neighbour-joining, maximum-parsimony maximum-likelihood, strains seawater inferred to be located in Halomonas aquamarina-meridiana clade family Halomonadaceae. Strains deep (5000-6000 m), however,...
Microbial communities in a shallow submarine hydrothermal system near Taketomi Island, Japan, were investigated using cultivation-based and molecular techniques. The main activity occurred craterlike basin (depth, approximately 23 m) on the coral reef seafloor. vent fluid (maximum temperature, >52 degrees C) contained 175 microM H2S gas bubbles mainly composed of CH4 (69%) N2 (29%). A liquid serial dilution cultivation technique targeting variety metabolism types quantified each population...
Two aerobic methane-oxidizing bacterial strains were isolated from distinct marine environments in Japan. Strains IT-4(T) and T2-1 Gram-stain-negative, aerobic, motile, plump short rods or oval-shaped bacteria with a single polar flagellum type I intracytoplasmic membranes. They obligate methanotrophs that grew only on methane methanol. Each strain possessed the particulate monooxygenase (pMMO). The ribulose monophosphate pathway was operative for carbon assimilation. best at 37 °C, did not...
A novel marine thermophilic and heterotrophic Anaerolineae bacterium in the phylum Chloroflexi, strain SW7T, was isolated from an situ colonization system deployed main hydrothermal vent of Taketomi submarine hot spring field located on southern part Yaeyama Archipelago, Japan. The microbial community associated with predominated by heterotrophs such as Thermococcaceae Anaerolineae, next dominant population sulfur oxidizers. Both aerobic anaerobic hydrogenotrophs including methanogens were...
A novel methane-oxidizing bacterium, strain IT-9(T), was isolated from a shallow submarine hydrothermal system occurring in coral reef Japan. Strain IT-9(T) Gram-negative, aerobic, motile, coccoid or oval-shaped bacterium with the distinctive intracytoplasmic membrane arrangement of type I methanotroph. moderately thermophilic, obligate methanotroph that grew on methane and methanol at 30-55 °C (optimum 45-50 °C). The possessed particulate monooxygenase (pMMO). ribulose monophosphate pathway...
The Integrated Ocean Drilling Program (IODP) Expedition 331 investigated the Iheya North hydrothermal field in Okinawa Trough. Several post‐drilling underwater vehicle investigations were conducted over 2 years to identify changes fluid discharge pattern, mineral deposition, and chemistry. Drilling‐induced high‐temperature vents identified at deep holes not only near naturally occurring NBC vent (Site C0016) but also seafloor ∼450 m distal C0014), where no was observed prior drilling. A...
For a rapid diagnosis of typhoid fever, we developed nested PCR based on the nucleotide sequence encoding Vi antigen. All Salmonella typhi strains along with paratyphi C strain were positive. This assay was able to detect S. at single-cell level.
Our survey of cooling tower water demonstrated that the highest density legionellae, ≥10 4 CFU/100 ml, appeared in containing protozoa, 2 MPN/100 and heterotrophic bacteria, 6 at temperatures between 25 35°C. Viable counts legionellae were detected even winter samples, propagation, up to 10 5 occurs summer. The correlated positively with increases temperature, pH, protozoan counts, but not bacterial counts. temperature towers may promote viable certain microbes, e.g., protozoa or some be a...
There has been an increasing interest in seafloor exploitation such as mineral mining deep-sea hydrothermal fields, but the environmental impact of anthropogenic disturbance to is poorly known. In this study, effect by scientific drilling operations (IODP Expedition 331) on seabed landscape and megafaunal habitation was surveyed for over 3 years using remotely operated vehicle video observation a field, Iheya North Okinawa Trough. We focused observations from particular site (Site C0014)...
Abstract Aim To characterize the species richness, endemism and community structure of benthic macro‐/megafauna in deep‐sea chemosynthetic ecosystems around Japanese archipelago determine conservation priority for habitats. Location Twenty‐seven methane seeps from Kuril–Japan Trench, Nankai Trough, Ryukyu Trench Sagami Bay as well 15 hydrothermal vents Izu–Bonin Arc Okinawa Trough archipelago. Methods Species richness number endemic 42 were examined using distributional data 155 mollusc,...
Abstract Three detection methods for Legionella species in water samples from cooling towers and a river were examined. Direct counting of bacteria stained with fluorescent antibody (FA) L. pneumophila (serogroups 1 to 6) could detect the cell 10 4 6 cell/100 ml all 14 samples, while colony method detected 3 CFU/100 only 8 towers. Polymerase chain reaction (PCR) assay primers amplify 16S ribosomal DNA sequence most (LEG primer) legionellae 13 species‐specific DNAs samples. In laboratory...
Viruses play important roles in marine surface ecosystems, but little is known about viral ecology and virus-mediated processes deep-sea hydrothermal microbial communities. In this study, we examined virus-like particle (VLP) abundances planktonic attached communities, which occur physical chemical gradients both deep shallow submarine environments (mixing waters between fluids ambient seawater dense communities to chimney areas or macrofaunal bodies colonies). We found that viruses were...
Abstract The benthic foraminifer Virgulinella fragilis Grindell and Collen 1976 has multiple putative symbioses with both bacterial kleptoplast endobionts, possibly aiding its survival in environments from dysoxia (5–45 μmol‐O 2 /L) to microxia (0–5 the dark. To clarify origin function of V. we used genetic analyses transmission electron microscope observations. retained δ‐proteobacteria concentrated at cell periphery just beneath membranes. Unlike another Stainforthia spp., which retains...
Abstract Hydrothermal vent fields are vulnerable to natural disturbances, such as volcanic activity, and currently being considered targets for mineral mining. Local communities linked by pelagic larval dispersal form regional metacommunities, nested within a number of biogeographic provinces. Larval supply depends on the connectivity networks, affects recoverability from disturbances. However, it is unclear how networks contribute local communities. Here, we integrated population dynamics...
The nonculturable form of Legionella pneumophila in multiple-nutrient starvation culture was studied. During extended starvation, the total direct counts (TDC) L. did not change significantly, but no colonies were detected on day 50. Quantitative PCR detection DNA demonstrated that cells retained PCR-detectable even after for 300 days, and part population possessed nonspecific esterase activity. However, resuscitation trials 100 recovered colony-forming units, electrophoresis nucleic acids...
For a rapid diagnosis of typhoid fever, we developed nested PCR based on the nucleotide sequence encoding Vi antigen. All Salmonella typhi strains along with paratyphi C strain were positive. This assay was able to detect S. at single-cell level.
An autonomous underwater vehicle (AUV) is an ideal platform that enables a closer approach to the seafloor than other platforms. The AUV provides remarkable advancement not only in imaging small‐scale bathymetry with high resolution but also spatial distribution of scattering signals within water column. Acoustic echoes can be recorded continuously by AUVs, potentially providing information related hydrothermal plumes In May 2007, such AUV, Urashima , Japan Agency for Marine–Earth Science...
The galatheid crab Shinkaia crosnieri , is the sole member of subfamily Shinkaiinae. It abundant and forms dense beds around active hydrothermal vents in Okinawa Trough. Thousands filamentous bacteria attached to plumose setae on ventral surface this were observed using field-emission scanning electron microscopy transmission microscopy. Nucleic acids extracted from bacteria, phylotypes 16S rRNA genes identified 81 clones. These divided into three groups: Epsilonproteobacteria (74%);...