Yasuhisa Asano

Bio: Yasuhisa Asano is an academic researcher from Toyama Prefectural University. The author has contributed to research in topics: Amino acid & Enzyme. The author has an hindex of 41, co-authored 347 publications receiving 6654 citations. Previous affiliations of Yasuhisa Asano include Dow Chemical Company & Kyoto University.

Aliphatic Nitrile Hydratase from Arthrobacter sp. J-1 Purification and Characterization

Abstract: A new enzyme, aliphatic nitrile hydratase, which hydrates acetonitrile to form acetamide was purified from the cell-free extract of acetonitrile-grown Arthrobacter sp. J-1. The overall purification was about 290-fold with a yield of 10%. The purified enzyme was homogeneous as judged by ultracentrifugation and disc gel electrophoresis. The enzyme catalyzed the stoichiometric hydration of acetonitrile to form acetamide according to the following scheme: CH3CN + H2O →. CH3CONH2. The enzyme was inducibly formed and then amidase which hydrolyzed acetamide was formed. The molecular weight of the enzyme was determined to be about 420,000 by gel filtration. The enzyme was composed of two kinds of subunits, of which the molecular weights were 24,000 and 27,000. The isoelectric point was 3.6. The enzyme was active toward low molecular weight aliphatic nitriles of 2 to 5 carbon atoms. The Km value for acetonitrile was determined to be 5.78 mM. The enzyme was inactivated by sulfhydryl reagents. The enzyme was competi...

A New Enzyme “Nitrile Hydratase” which Degrades Acetonitrile in Combination with Amidase

Abstract: (1980). A New Enzyme “Nitrile Hydratase” which Degrades Acetonitrile in Combination with Amidase. Agricultural and Biological Chemistry: Vol. 44, No. 9, pp. 2251-2252.

A new enzymatic method of acrylamide production.

Abstract: To produce acrylamide from acrylonitrile by use of a new enzyme, nitrile hydratase, a number of nitrile-utilizing microorganisms were screened for the enzyme activity by an intact cell system. An isobutyronitrile-utilizing bacterium, strain B23, showed the best productivity among 186 strains tested. The strain was identified taxonomically as Pseudomonas chlor or aphis. The culture and reaction conditions for the production were studied for the strain. Under the optimum conditions, 400 grams/liter of acrylamide was produced in 7.5 hr. The yield was nearly 100% with a trace amount of acrylic acid. The cell-free extract of the strain showed strong activity of nitrile hydratase toward acrylonitrile and extremely low activity of amidase toward acrylamide.

Novel Heme-Containing Lyase, Phenylacetaldoxime Dehydratase from Bacillus sp. Strain OxB-1: Purification, Characterization, and Molecular Cloning of the Gene†,‡

Abstract: A novel dehydratase that catalyzes the stoichiometric dehydration of Z-phenylacetaldoxime to phenylacetonitrile has been purified 483-fold to homogeneity from a cell-free extract of Bacillus sp. st...

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Engineering the third wave of biocatalysis

Abstract: Over the past ten years, scientific and technological advances have established biocatalysis as a practical and environmentally friendly alternative to traditional metallo- and organocatalysis in chemical synthesis, both in the laboratory and on an industrial scale. Key advances in DNA sequencing and gene synthesis are at the base of tremendous progress in tailoring biocatalysts by protein engineering and design, and the ability to reorganize enzymes into new biosynthetic pathways. To highlight these achievements, here we discuss applications of protein-engineered biocatalysts ranging from commodity chemicals to advanced pharmaceutical intermediates that use enzyme catalysis as a key step.

Next Generation of Fluorine-Containing Pharmaceuticals, Compounds Currently in Phase II–III Clinical Trials of Major Pharmaceutical Companies: New Structural Trends and Therapeutic Areas

Abstract: Compounds Currently in Phase II−III Clinical Trials of Major Pharmaceutical Companies: New Structural Trends and Therapeutic Areas Yu Zhou,† Jiang Wang,† Zhanni Gu,† Shuni Wang,† Wei Zhu,† Jose ́ Luis Aceña,*,‡,§ Vadim A. Soloshonok,*,‡,∥ Kunisuke Izawa,* and Hong Liu*,† †Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China ‡Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizab́al 3, 20018 San Sebastiań, Spain Department of Organic Chemistry, Autońoma University of Madrid, Cantoblanco, 28049 Madrid, Spain IKERBASQUE, Basque Foundation for Science, María Díaz de Haro 3, 48013 Bilbao, Spain Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, Japan 533-0024

The chemistry and biochemistry of vanadium and the biological activities exerted by vanadium compounds.

Abstract: 6.1.2. Aqueous V(III) Chemistry 877 6.1.3. Oxidation State of Vanadium in Tunicates 878 6.1.4. Uptake of Vanadate into Tunicates 879 6.1.5. Vanadium Binding Proteins: Vanabins 879 6.1.6. Model Complexes and Their Chemistry 880 6.1.7. Catechol-Based Model Chemistry 880 6.1.8. Vanadium Sulfate Complexes 881 6.2. Fan Worm Pseudopotamilla occelata 883 7. Vanadium Nitrogenase 883 7.1. Nitrogenases 883 7.2. Biochemistry of Nitrogenase 884 7.3. Clusters in Nitrogenase and Model Systems: Structure and Reactivity 885