title: Confirming the revised C-terminal domain of the MscL crystal structure.
abstract: The structure of the C-terminal domain of the mechanosensitive channel of large conductance (MscL) has generated significant controversy. As a result, several structures have been proposed for this region: the original crystal structure (1MSL) of the Mycobacterium tuberculosis homolog (Tb), a model of the Escherichia coli homolog, and, most recently, a revised crystal structure of Tb-MscL (2OAR). To understand which of these structures represents a physiological conformation, we measured the impact of mutations to the C-terminal domain on the thermal stability of Tb-MscL using circular dichroism and performed molecular dynamics simulations of the original and the revised crystal structures of Tb-MscL. Our results imply that this region is helical and adopts an alpha-helical bundle conformation similar to that observed in the E. coli MscL model and the revised Tb-MscL crystal structure.
authors.affiliation: Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA. maurer@wustl.edu
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Maurer
authors.forename: Donald E
authors.initials: DE
authors.lastname: Elmore
authors.forename: Daniel
authors.initials: D
authors.lastname: Clayton
authors.forename: Li
authors.initials: L
authors.lastname: Xiong
authors.forename: Henry A
authors.initials: HA
authors.lastname: Lester
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Dougherty
mesh_terms: D003198:Computer Simulation; D003461:Crystallography / Q000379:methods; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000648:ultrastructure*; D007473:Ion Channels / Q000737:chemistry* / Q000648:ultrastructure*; D008956:Models, Chemical; D008958:Models, Molecular; D011487:Protein Conformation; D017434:Protein Structure, Tertiary
chemical_list: D029968:Escherichia coli Proteins; D007473:Ion Channels; C086596:MscL protein, E coli