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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.

SUBMITTER: Maurer JA

PROVIDER: S-EPMC2397327 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Confirming the revised C-terminal domain of the MscL crystal structure.

Maurer Joshua A JA Elmore Donald E DE Clayton Daniel D Xiong Li L Lester Henry A HA Dougherty Dennis A DA

Biophysical journal 20080307 12

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 imp ...[more]

PMID: 18326638

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