title: Protein crystals and their evil twins.
abstract: Different types of crystal twinning are reviewed with an emphasis on how to detect the phenomenon from protein diffraction data. The recent literature and a database survey both serve as reminders to perform routine checks whenever twinning is a possibility.
authors.affiliation: UCLA Department of Chemistry and Biochemistry, DOE Laboratory of Structural Biology and Molecular Medicine, 405 Hilgard Avenue, Box 951569, Los Angeles CA 90095-1569, USA. yeates@mbi.ucla.edu
authors.forename: T O
authors.initials: TO
authors.lastname: Yeates
authors.forename: B C
authors.initials: BC
authors.lastname: Fam
mesh_terms: D001436:Bacteriorhodopsins / Q000737:chemistry; D003460:Crystallization; D016208:Databases, Factual; D011506:Proteins / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D011506:Proteins; D001436:Bacteriorhodopsins