title: Conformational stability and crystal packing: polymorphism in Neurospora crassa CAT-3.
abstract: Polymorphism is frequently observed from different crystallization conditions. In proteins, the effect on conformational variability is poorly documented, with only a few reported examples. Here, three polymorphic crystal structures determined for a large-subunit catalase, CAT-3 from Neurospora crassa, are reported. Two of them belonged to new space groups, P1 and P43212, and a third structure belonged to the same space group, P212121, as the previously deposited 2.3 Å resolution structure (PDB entry 3ej6), but had a higher resolution (1.95 Å). Comparisons between these polymorphic structures highlight the conformational stability of tetrameric CAT-3 and reveal a distortion in the tetrameric structure that has not previously been described.
authors.affiliation: Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Avenida Universidad 2001, Chamilpa, 62210 Cuernavaca, MOR, Mexico. anzaro@ibt.unam.mx
authors.forename: Andrés
authors.initials: A
authors.lastname: Zárate-Romero
authors.forename: Vivian
authors.initials: V
authors.lastname: Stojanoff
authors.forename: Sonia Patricia
authors.initials: SP
authors.lastname: Rojas-Trejo
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Hansberg
authors.forename: Enrique
authors.initials: E
authors.lastname: Rudiño-Piñera
mesh_terms: D002374:Catalase / Q000737:chemistry* / Q000145:classification / Q000235:genetics; D003460:Crystallization; D018360:Crystallography, X-Ray; D004795:Enzyme Stability; D008958:Models, Molecular; D008968:Molecular Conformation; D009492:Neurospora crassa / Q000201:enzymology* / Q000235:genetics; D011487:Protein Conformation; D055503:Protein Multimerization; D011994:Recombinant Proteins / Q000737:chemistry* / Q000145:classification / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D002374:Catalase