title: Purification, crystallization, crystallographic analysis and phasing of the CRISPR-associated protein Csm2 from Thermotoga maritima.
abstract: The clusters of regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated proteins (Cas) system consists of an intriguing machinery of proteins that confer bacteria and archaea with immunity against phages and plasmids via an RNA-guided interference mechanism. Here, the cloning, recombinant expression in Escherichia coli BL21 (DE3), purification, crystallization and preliminary X-ray diffraction analysis of Csm2 from Thermotoga maritima are reported. Csm2 is thought to be a component of an important protein complex of the type IIIA CRISPR-Cas system, which is involved in the CRISPR-Cas RNA-guided interference pathway. The structure of Csm2 was solved via cadmium single-wavelength anomalous diffraction (Cd-SAD) phasing. Owing to its involvement in the CRISPR-Cas system, the crystal structure of this protein could be of importance in elucidating the mechanism of type IIIA CRISPR-Cas systems in bacteria and archaea.
authors.affiliation: Department of Science and Technology, Federal University of São Paulo, Rua Talim 330, 12231-280 São José dos Campos-SP, Brazil.
authors.forename: Gloria
authors.initials: G
authors.lastname: Gallo
authors.affiliation: Department of Science and Technology, Federal University of São Paulo, Rua Talim 330, 12231-280 São José dos Campos-SP, Brazil.
authors.forename: Gilles
authors.initials: G
authors.lastname: Augusto
authors.affiliation: Department of Science and Technology, Federal University of São Paulo, Rua Talim 330, 12231-280 São José dos Campos-SP, Brazil.
authors.forename: Giulliana
authors.initials: G
authors.lastname: Rangel
authors.affiliation: Department of Science and Technology, Federal University of São Paulo, Rua Talim 330, 12231-280 São José dos Campos-SP, Brazil.
authors.forename: André
authors.initials: A
authors.lastname: Zelanis
authors.affiliation: Department of Biophysics, Federal University of São Paulo, Rua Botucatu 862, 04023-062 São Paulo-SP, Brazil.
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: Mori
authors.affiliation: Department of Science and Technology, Federal University of São Paulo, Rua Talim 330, 12231-280 São José dos Campos-SP, Brazil.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Barbosa Campos
authors.affiliation: Department of Science and Technology, Federal University of São Paulo, Rua Talim 330, 12231-280 São José dos Campos-SP, Brazil.
authors.forename: Martin
authors.initials: M
authors.lastname: Würtele
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D064130:CRISPR-Associated Proteins / Q000737:chemistry* / Q000302:isolation & purification; D002850:Chromatography, Gel; D003460:Crystallization; D018360:Crystallography, X-Ray; D055672:Static Electricity; D020124:Thermotoga maritima / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D064130:CRISPR-Associated Proteins
keywords: CRISPR–Cas; Csm2; RNA-guided interference; Thermotoga maritima