title: Crystallization and preliminary X-ray studies of the Ia component of Clostridium perfringens iota toxin complexed with NADPH.
abstract: A recombinant Ia component of Clostridium perfringens iota toxin, which ADP-ribosylates actin, was crystallized by the hanging drop vapor diffusion method using PEG4000 as a precipitating agent. The crystals were obtained in the presence of NADPH, which is similar to a real substrate, NADH, and belongs to the space group P1 (a = 47.9 A, b = 54.5 A, c = 103.1 A, alpha = 99.0 degrees, beta = 93.3 degrees, and gamma = 107.2 degrees ). The Matthews coefficient of native crystal was 2.7, assuming 2 mol/asymmetric unit. Native data were collected at 2.4-A resolution. The results from a heavy-atom search showed that lanthanide ions (samarium, holmium) altered the molecular packing, judging from the unit-cell difference. The crystals also belonged to the space group P1 (a = 47.7 A, b = 53.9 A, c = 54.6 A, alpha = 68.9 degrees, beta = 78.3 degrees, and gamma = 73.7 degrees ), which is consistent with only one molecule per asymmetric unit.
authors.affiliation: Institute for Health Science, Tokushima Bunri University, Tokushima, Yamashiro-cho, 770-8514, Japan. tsuge@tokushima.bunri-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Tsuge
authors.forename: M
authors.initials: M
authors.lastname: Nagahama
authors.forename: T
authors.initials: T
authors.lastname: Nishimura
authors.forename: Y
authors.initials: Y
authors.lastname: Sakaguchi
authors.forename: N
authors.initials: N
authors.lastname: Katunuma
authors.forename: J
authors.initials: J
authors.lastname: Sakurai
mesh_terms: D036002:ADP Ribose Transferases; D001426:Bacterial Proteins / Q000737:chemistry; D001427:Bacterial Toxins / Q000737:chemistry*; D003016:Clostridium perfringens / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray; D008859:Microscopy, Polarization; D009249:NADP / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; C050737:iota toxin, Clostridium perfringens; D011092:Polyethylene Glycols; D009249:NADP; D036002:ADP Ribose Transferases