A5020181766- Microbial Community Ecology and Physiology
- Genomics and Phylogenetic Studies
- Methane Hydrates and Related Phenomena
- Enzyme Production and Characterization
- Protist diversity and phylogeny
- Metal Extraction and Bioleaching
- Algal biology and biofuel production
- Wastewater Treatment and Nitrogen Removal
- Biocrusts and Microbial Ecology
- Mine drainage and remediation techniques
- Catalysis for Biomass Conversion
- Enzyme Catalysis and Immobilization
- Antibiotic Resistance in Bacteria
- Phytoplasmas and Hemiptera pathogens
- Legume Nitrogen Fixing Symbiosis
- Calcium Carbonate Crystallization and Inhibition
- Silk-based biomaterials and applications
- Microbial Metabolic Engineering and Bioproduction
- Antioxidant Activity and Oxidative Stress
- Free Radicals and Antioxidants
- Biofuel production and bioconversion
- Studies on Chitinases and Chitosanases
- Phytase and its Applications
- Plant Reproductive Biology
- Marine and coastal ecosystems
Toyo University
2005-2022
RIKEN
1992-1994
Tokyo Institute of Technology
1992
RIKEN Center for Brain Science
1988
The carotenoids produced by extremely halophilic archaeon Haloarcula japonica were extracted and identified their chemical, chromatographic, spectroscopic characteristics (UV-Vis mass spectrometry). composition (mol%) was 68.1% bacterioruberin, 22.5% monoanhydrobacterioruberin, 9.3% bisanhydrobacterioruberin, <0.1% isopentenyldehydrorhodopin, trace amounts of lycopene phytoene. in vitro scavenging capacity a carotenoid, from cells against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals...
An iron-reducing, moderately thermophilic, acidophilic actinobacterium, strain IC-180 T , isolated from a solfataric field in Hakone, Japan, was subjected to polyphasic taxonomic analysis. Strain motile, short rod-shaped, Gram-positive bacterium that able grow at temperatures of 35–58 °C (optimally 50 °C) and pH 2.0–4.5 3.0). The grew aerobically heterotrophically. It also anaerobically or autotrophically by dissimilatory reduction ferric iron. No oxidation ferrous iron observed. Major...
A novel thermoacidophilic, cell wall-less archaeon, strain IC-189T, was isolated from a solfataric field in Ohwaku-dani, Hakone, Japan. The cells were irregular cocci, sometimes lobed, club-shaped or catenated, and highly variable size, ranging 0.8 to 8.0 microm diameter. grew at temperatures the range 38-68 degrees C (optimally 60 C) pH 1.8-4.0 around 3.0). Strain IC-189T obligately aerobic heterotrophic, requiring yeast extract for growth. Yeast extract, glucose mannose served as carbon...
A co-culture of a novel thermoacidophilic, obligate symbiotic archaeon, designated as strain MJ1T, with its specific host archaeon Metallosphaera sedula MJ1HA was obtained from terrestrial hot spring in Japan. Strain MJ1T grew the under aerobic conditions. Coccoid cells were 200-500 nm diameter, and attached to co-culture. The ranges optima growth temperature pH 60-75 °C (optimum, 65-70 °C) 1.0-4.0 2.5), respectively. Core lipids dialkyl glycerol tetraethers (GDGT)-3 GDGT-4 highly abundant...
A novel moderately thermophilic, weakly acidophilic, heterotrophic, anaerobic, short-rod bacterium having an outer sheath-like structure (toga) was isolated from a low-salt acidic terrestrial hot spring in Oku-Shiobara, Tochigi, Japan. The strain, designated NAS-01T, grew between 30 and 60 °C (optimum 55 °C), at pH 4.5 7.5 5.5 to 6.0) could not grow media with ≥ 1 % NaCl 0 NaCl). It utilized Fe(III), thiosulfate or l-cystine as electron acceptor for growth, yeast extract, peptone variety of...
Two novel, strictly aerobic, sulfur-dependent, thermoacidophilic strains, IC-006T and IC-007, were isolated from a solfataric field at Hakone Ohwaku-dani, Kanagawa, Japan. Cells of the two strains irregular cocci with diameter 1.0-1.8 µm. They strict aerobes grew in temperature range between 45 69 °C (optimally 65 °C) pH 0.4 5.5 3.5). required sulfur or reduced compound, was oxidized to sulfate. autotrophically mixotrophically utilizing several sugars complex organic substances as carbon...
Haloarcula japonica is an extremely halophilic archaeon that requires high concentrations of NaCl to grow. Recently the draft genome sequence Ha. was determined, and a gene encoding α-amylase, malA, identified. The deduced amino acid MalA, consisting 663 acids, showed homology α-amylase family enzymes. did not contain secretion signal sequence, indicating protein cytoplasmic enzyme. Transcription malA confirmed by reverse transcription (RT)-PCR, start site determined 5'-RACE experiment....
A thermoacidophilic, anaerobic, and iron- sulfur-reducing archaeon, strain NAS-02 T , was isolated from a terrestrial hot spring in Japan, as previously reported. This organism is the first non-ammonia-oxidizing isolate phylum Thaumarchaeota . Here, we propose Conexivisphaera calida gen. nov., sp. nov. to accommodate this strain. The type of species (=JCM 31663 =DSM 105898 ). values 16S rRNA gene similarity average amino acid identity between its closest relatives are <86 <42 %,...
The cell division of the halophilic archaebacterium, Haloarcula japonicus, which has a characteristic triangular shape in high salt concentration media, was analysed by time lapse microscopic cinematography. Cell on an agar medium occured average every 3.7 h. plates were laid down asymmetrically, generating or rhomboid daughter cells then separated. plate formation clearly observed because are flat and thin enough to see through using conventional light microscope.
Journal Article The Cell Surface Glycoprotein of Haloarcula japonica TR-1 Get access Satoshi Nakamura, Nakamura Department Bioengineering, Faculty Bioscience and Biotechnology, Tokyo Institute Technology, Midori-ku, Yokohama 227, Japan Correspondence to: S. 4259 Nagatsuta, Japan. Search for other works by this author on: Oxford Academic Google Scholar Rikizo Aono, Aono Shin Mizutani, Mizutani Tomonori Takashina, Takashina JapanThe Superbugs Project, c/o RIKEN Institute, Wako-shi, Saitama...
Cells of the halophilic archaebacterium Haloarcula japonica strain TR-1 were prepared for electron microscopy using conventional fixation and freeze-substitution method. Cell walls not observed in thin sections cells by procedures, whereas method revealed a cell wall 20–25 nm thickness composed three layers. Arrays hexagonal structures arranged on surface grazing sections.
An open reading frame encoding a chitinase homolog (ChiN1) was found in the genome of extremely halophilic archaeon Halobacterium salinarum NRC-1. ChiN1 is multidomain enzyme consisting chitin-binding domain, polycystic kidney disease domain and catalytic belonging to glycoside hydrolase family 18. chiN1 gene successfully expressed Haloarcula japonica TR-1 by employing promoter sequence its cell surface glycoprotein gene. A large amount recombinant secreted into culture supernatant. The Ha....
An open reading frame encoding an aerotaxis transducer HemAT homolog (named HemAT-Hj) was found in the genome of extremely halophilic archaeon Haloarcula japonica TR-1. HemAT-Hj would be a cytoplasmic protein consisting sensor domain, linker region and methyl-accepting signaling domain. The hemAT-Hj gene successfully expressed Escherichia coli. Recombinant purified characterized. Absorption spectra showed that E. coli-produced contained b-type heme molecule.
In the light of significance extremophiles as model organisms to access possible extraterrestiral life, we provide a short review systematics thermophilic Archaea, and introduce our exploratory research novel Archaea from hot springs in Japan. Up date, have isolated 162 strains Japan by enrichment method or most probable number/PCR method, 16S rRNA gene sequences were determined reveal their phylogenetic diversity. The sequence comparison illustrated that isolates belonged orders...