Inward facing conformations of the MetNI methionine ABC transporter: Implications for the mechanism of transinhibition.

ABSTRACT: Two new crystal structures of the Escherichia coli high affinity methionine uptake ATP Binding Cassette (ABC) transporter MetNI, purified in the detergents cyclohexyl-pentyl-β-D-maltoside (CY5) and n-decyl-β-D-maltopyranoside (DM), have been solved in inward facing conformations to resolutions of 2.9 and 4.0 Å, respectively. Compared to the previously reported 3.7 Å resolution structure of MetNI purified in n-dodecyl-β-D-maltopyranoside (DDM), the higher resolution of the CY5 data enabled significant improvements to the structural model in several regions, including corrections to the sequence registry, and identification of ADP in the nucleotide binding site. CY5 crystals soaked with selenomethionine established details of the methionine binding site in the C2 regulatory domain of the ABC

SUBMITTER: Johnson E 

PROVIDER: S-EPMC3323783 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature