Crystal structure of endo-1,4--glucanase from

Arimori, Takao*; Ito, Akihiro*; Nakazawa, Masami*; Ueda, Mitsuhiro*; Tamada, Taro

Journal of Synchrotron Radiation, 20(6), p.884 - 889, 2013/11

https://doi.org/10.1107/S0909049513021110

The saccharification process is essential for bioethanol production from woody biomass including celluloses. Cold-adapted cellulase, which has sufficient activity at low temperature ( 293 K), is capable of reducing heating costs during the saccharification process and is suitable for simultaneous saccharification and fermentation. Endo-1,4--glucanase from the earthworm Eisenia fetida (EF-EG2) belonging to glycoside hydrolase family 9 has been shown to have the highest activity at 313 K, and also retained a comparatively high activity at 283 K. The recombinant EF-EG2 was purified expressed in Pichia pastoris, and then grew needle-shaped crystals with dimensions of 0.02 0.02 1 mm. The crystals belonged to the space group P3221 with unit-cell parameters of = =136 , = 55.0 ,. The final model of EF-EG2, including 435 residues, two ions, seven crystallization reagents and 696 waters, was refined to a crystallographic -factor of 14.7% (free -factor of 16.8%) to 1.5 , resolution. The overall structure of EF-EG2 has an (/) barrel fold which contains a putative active-site cleft and a negatively charged surface. This structural information helps us understand the catalytic and cold adaptation mechanisms of EF-EG2.

Crystallization and preliminary X-ray diffraction studies of the catalytic domain of a novel chitinase, a member of GH family 23, from the moderately thermophilic bacterium sp. A-471

Okazaki, Nobuo; Arimori, Takao; Nakazawa, Masami*; Miyatake, Kazutaka*; Ueda, Mitsuhiro*; Tamada, Taro

Acta Crystallographica Section F, 67(4), p.494 - 497, 2011/04

https://doi.org/10.1107/S1744309111004751

Recent progress in the energy recovery linac project in Japan

Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05

http://accelconf.web.cern.ch/AccelConf/IPAC10/papers/tupe091.pdf

Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.

Crystal structure of 1,4--endoglucanase from

Arimori, Takao*; Ito, Akihiro*; Nakazawa, Masami*; Ueda, Mitsuhiro*; Tamada, Taro

no journal, , 

no abstracts in English

Crystal structure of a novel chitinase from Ralstonia sp. A-471

Arimori, Takao; Okazaki, Nobuo; Nakazawa, Masami*; Miyatake, Kazutaka*; Ueda, Mitsuhiro*; Tamada, Taro

no journal, , 

no abstracts in English

Study on release and transport of aerial radioactive materials in reprocessing plant, 1; Background and event of study

Ueda, Yoshinori*; Takanashi, Mitsuhiro*; Uchiyama, Gunzo; Yoshida, Kazuo; Yamane, Yuichi; Sekine, Keiji*; Fujita, Kunio*

no journal, , 

A study on the release and transport of aerial radioactive materials in reprocessing plants was stared to develop risk assessment methods. The background and event of study will be presented.

Crystal structure of a cold-adapted cellulase

Tamada, Taro; Arimori, Takao*; Fukuhara, Hiroaki*; Ito, Akihiro*; Ueda, Mitsuhiro*

no journal, , 

The saccharification process is essential for bioethanol production from woody biomass including celluloses. Cold-adapted cellulase, which has sufficient activity at low temperature ( 293 K), is capable of reducing heating costs during the saccharification process and is suitable for simultaneous saccharification and fermentation. Endo-1,4--glucanase from the earthworm Eisenia fetida (EF-EG2) belonging to glycoside hydrolase family 9 has been shown to have the highest activity at 313 K, and also retained a comparatively high activity at 283 K. The recombinant EF-EG2, expressed in , was purified and then grew needle-shaped crystals with dimensions of 0.02 0.02 1 mm. The final model of EF-EG2, including 435 residues, two ions, seven crystallization reagents and 696 waters, was refined to a crystallographic -factor of 14.7% (free -factor of 16.8%) to 1.5 resolution. The overall structure of EF-EG2 has an(/) barrel fold which contains a putative active-site cleft and a negatively charged surface. Furthermore, in the structure of the E431Q mutant of EF-EG2 complexed with cellotriose (CTR), electron densities corresponding to CTR are observed well at -4 to -2 subsites. This structural information helps us understand the catalytic and cold adaptation mechanisms of EF-EG2.

Development of new reduced activation HEAs by additive manufacturing method, 1; Outline

Hashimoto, Naoyuki*; Ueda, Mikito*; Hayashi, Shigenari*; Oka, Hiroshi*; Isobe, Shigehito*; Yamashita, Shinichiro; Itakura, Mitsuhiro; Tsuru, Tomohito

no journal, , 

The objective of this work is the development of new reduced activation HEAs applicable to next generation small module reactor components by using additive manufacturing (3D printing) method under the support of the 2020 MEXT Innovative Nuclear Research and Development Program. We firstly introduce the outline of this work as a part of the series presentation.

Crystal structure of Ra-ChiC belonging to GH family 23

Arimori, Takao; Kawamoto, Noriko*; Okazaki, Nobuo; Nakazawa, Masami*; Miyatake, Kazutaka*; Ueda, Mitsuhiro*; Tamada, Taro

no journal, , 

no abstracts in English

Crystal structures of the catalytic domain of a novel chitinase belonging to GH family 23

Arimori, Takao*; Kawamoto, Noriko*; Okazaki, Nobuo*; Nakazawa, Masami*; Miyatake, Kazutaka*; Fukamizo, Tamo*; Ueda, Mitsuhiro*; Tamada, Taro

no journal, , 

Chitin, linear -1,4-linked polymer of -acetyl-D-glucosamine (NAG), is the second abundant biopolymer in nature next to cellulose. Hydrolysis of chitin provides useful products, -acetyl-chitooligosaccharides [(NAG)] and chitooligosaccharides, which have a variety of biological functions including antibacterial activity and antitumor activity. We have previously cloned a novel chitinase gene from a moderate thermophilic strain sp. A-471 (Ra-ChiC). Ra-ChiC comprises a signal peptide, a chitin-binding domain, an interdomain linker, and a catalytic domain. The catalytic domain shares amino acid sequence homology with goose type (G-type) lysozymes and, unlike other chitinases, Ra-ChiC belongs to glycohydrolase (GH) family 23. However, Ra-ChiC does not exhibit lysozyme activity, but only chitinase activity. In this study, we aim to reveal how Ra-ChiC catalyzes the hydrolysis of chitin and why Ra-ChiC exhibits chitinase activity instead of lysozyme activity. We determined the crystal structures of the catalytic domain of Ra-ChiC (Ra-ChiC), Ra-ChiC complexed with (NAG), E141Q mutant of Ra-ChiC complexed with (NAG), E162Q mutant of Ra-ChiC, and E162Q mutant of Ra-ChiC complexed with (NAG). These structures provided us structural basis of substrate recognition mechanism and revealed that Ra-ChiC has a unique substrate-binding site including a tunnel-shaped cavity, which determines the substrate specificity. In addition, we also carried out a mutation analysis of acidic amino acid residues located at the active site. As a result, we found that not only a highly conserved Glu141 but also Asp226 located at the roof of the tunnel have quite important roles in catalysis.