Time filter

Source Type

Yasumoto K.,Kitasato University | Yasumoto-Hirose M.,Tropical Technology Center Ltd | Yasumoto J.,University of Ryukyus | Murata R.,Kitasato University | And 7 more authors.
Marine Biotechnology | Year: 2014

Bacteria, including cyanobacteria, as well as some fungi, are known to deposit calcium carbonate (CaCO3) extracellularly in calcium-containing artificial medium. Despite extensive investigation, the mechanisms involved in extracellular formation of CaCO3 by bacteria have remained unclear. The ability of synthetic amines to remove carbon dioxide (CO2) from natural gas led us to examine the role of biogenic polyamines in CaCO3 deposition by bacteria. Here, we demonstrated that biogenic polyamines such as putrescine, spermidine, and spermine were able to react with atmospheric CO2 and the resultant carbamate anion was characterized by using nuclear magnetic resonance (NMR) analysis. Biogenic polyamines accelerated the formation of CaCO3, and we artificially synthesized the dumbbell-shaped calcites, which had the same form as observed with bacterial CaCO3 precipitates, under nonbacterial conditions by using polyamines. The reaction rate of calcification increased with temperature with an optimum of around 40 °C. Our observation suggests a novel scheme for CO2 dissipation that could be a potential tool in reducing atmospheric CO2 levels and, therefore, global warming. © 2014 Springer Science+Business Media New York. Source

Zheng H.-J.,Shanghai Institute of Planned Parenthood Research | Zheng H.-J.,Chinese National Human Genome Center at Shanghai | Tsukahara M.,Tropical Technology Center Ltd | Liu E.,Shanghai Institute of Planned Parenthood Research | And 6 more authors.
Stem Cells and Development | Year: 2015

The gene trap method for embryonic stem cells is an efficient method for identifying new genes that are involved in development. Using this method, we identified a novel gene called helicase family gene related to gastrulation (helG). Helicase family proteins regulate many systems in the body that are related to cell survival. HelG encodes a protein of 137kDa, which contains a DExH helicase motif that is now named DHX30. HelG is strongly expressed in neural cells (ie, in the headfold, neural plate, neural tube, and brain) and somites during embryogenesis. Growing homozygous mutant embryos have neither differentiated somites nor brains. In these mutants, development was retarded by embryonic day 7.5 (E7.5), and the mutants died at E9.5. After the purification of HelG, an untwisting experiment was performed to confirm the helicase activity of HelG for DNA in vitro. We report for the first time that a helicase family gene is required for differentiation during embryogenesis; this gene might interact with polynucleotides to regulate some genes that are important for early development and has a structure similar to that of a human DExH box helicase. © Copyright 2015, Mary Ann Liebert, Inc. Source

Ikehara T.,Tropical Technology Center Ltd | Imamura S.,Tropical Technology Center Ltd | Yoshino A.,Tropical Technology Center Ltd | Yasumoto T.,Okinawa Institute of Science and Technology
Toxins | Year: 2010

Okadaic acid and its analogs (OAs) responsible for diarrhetic shellfish poisoning (DSP) strongly inhibit protein phosphatase 2A (PP2A) and thus are quantifiable by measuring the extent of the enzyme inhibition. In this study, we evaluated the suitability of the catalytic subunit of recombinant human PP2A (rhPP2Ac) for use in a microplate OA assay. OA, dinophysistoxin-1(DTX1), and hydrolyzate of 7-O-palmitoyl-OA strongly inhibited rhPP2Ac activity with IC 50 values of 0.095, 0.104, and 0.135 nM, respectively. The limits of detection and quantitation for OA in the digestive gland of scallops and mussels were 0.0348 μg/g and 0.0611 μg/g respectively, and, when converted to the whole meat basis, are well below the regulation level proposed by EU (0.16 μg/g whole meat). A good correlation with LC-MS data was demonstrated, the correlation coefficient being 0.996 with the regression slope of 1.097. © 2010 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland. Source

TROPICAL TECHNOLOGY CENTER Ltd. and University of Ryukyus | Date: 2010-04-06

A therapeutic agent comprising fucoxanthin or fucoxanthinol as an active component is disclosed. The therapeutic agent is effective and high clinical utility for medical treatment and prevention of virus-associated malignancy such as adult T-cell leukemia and Burkitt lymphoma.

Umemura M.,Japan National Institute of Advanced Industrial Science and Technology | Koike H.,Japan National Institute of Advanced Industrial Science and Technology | Yamane N.,Japan National Institute of Advanced Industrial Science and Technology | Koyama Y.,Japan National Institute of Advanced Industrial Science and Technology | And 13 more authors.
DNA Research | Year: 2012

Aspergillus oryzae has been utilized for over 1000 years in Japan for the production of various traditional foods, and a large number of A. oryzae strains have been isolated and/or selected for the effective fermentation of food ingredients. Characteristics of genetic alterations among the strains used are of particular interest in studies of A. oryzae. Here, we have sequenced the whole genome of an industrial fungal isolate, A. oryzae RIB326, by using a next-generation sequencing system and compared the data with those of A. oryzae RIB40, a wild-type strain sequenced in 2005. The aim of this study was to evaluate the mutation pressure on the non-syntenic blocks (NSBs) of the genome, which were previously identified through comparative genomic analysis of A. oryzae, Aspergillus fumigatus, and Aspergillus nidulans. We found that genes within the NSBs of RIB326 accumulate mutations more frequently than those within the SBs, regardless of their distance from the telomeres or of their expression level. Our findings suggest that the high mutation frequency of NSBs might contribute to maintaining the diversity of the A. oryzae genome. © 2012 The Author. Source

Discover hidden collaborations