著者
吉田 徹 山田 等仁 津下 英明
出版者
日本結晶学会
雑誌
日本結晶学会誌 (ISSN:03694585)
巻号頁・発行日
vol.64, no.1, pp.69-76, 2022-02-28 (Released:2022-03-04)
参考文献数
20

The iota toxin produced by Clostridium perfringens type E is a binary toxin comprising two independent polypeptides:Ia, an ADP-ribosyltransferase, and Ib, which is involved in cell binding and translocation of Ia across the cell membrane. Binary toxin family includes C. perfringens iota toxin, C. difficile CDT, C. spiroforme CST, C. botulinum C2, and B. anthracis anthrax toxin. Here we introduce the binary toxin complex structures using single-particle Cryo-EM structural analysis and the structural basis of toxin translocation system.
著者
津下 英明
出版者
一般社団法人 日本生物物理学会
雑誌
生物物理 (ISSN:05824052)
巻号頁・発行日
vol.43, no.4, pp.168-173, 2003 (Released:2003-07-23)

The family of mono-ADP-ribosyltransferase includes not only bacterial toxins but also mammalian enzymes. Recently, crystal structures of arginine-specific ADP-ribosyltransferase have been revealed, giving a better understanding of type IV toxin. They are VIP2 from Bacillus and Ia from Clostridium perfringens. VIP2 and Ia ADP-ribosylate the Arg177 of actin. They consist of topologically similar N- and C-domains, which have not been expected from the amino acid sequence. C-domain is an enzymatic domain. N-domain interacts with VIP1 and Ib, respectively. C-domain structures were basically the same but the surface charge of N-domain was found significantly different between VIP2 and Ia. Rat ART2.2 and rho-targeted C3 toxin(asparagine-specific)consist of only one domain and the structure is similar to the C-domain of Ia. We summarize the crystal structure and the reaction mechanism of Ia.
著者
津下 英明
出版者
一般社団法人日本生物物理学会
雑誌
生物物理 (ISSN:05824052)
巻号頁・発行日
vol.43, no.4, pp.168-173, 2003-07-25

モノADPリボシルトランスフェラーゼ群として,細菌のモノADPリボシル化毒素と哺乳類モノADPリボシル化酵素が大きなファミリーを形成している.最近タイプIVの毒素に属するアクチンを標的とするアルギニン特異的なVIP2とla,さらにタイプIIIのRhoをADPリボシル化するC3およびラットART2.2の構造が明らかにされた.本稿ではla-NADH複合体の結晶構造とADPリボシル化の反応機構について解説する.