GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.
PMID:19324881
| Citation |
Hernández, A, Maté, MJ, Sánchez-Díaz, PC, Romero, A, Rojo, F and Martínez, JL (2009) Structural and functional analysis of SmeT, the repressor of the Stenotrophomonas maltophilia multidrug efflux pump SmeDEF. J. Biol. Chem. 284:14428-38 |
|---|---|
| Abstract |
Stenotrophomonas maltophilia is an opportunistic pathogen characterized for its intrinsic low susceptibility to several antibiotics. Part of this low susceptibility relies on the expression of chromosomally encoded multidrug efflux pumps, with SmeDEF being the most relevant antibiotic resistance efflux pump so far studied in this bacterial species. Expression of smeDEF is down-regulated by the SmeT repressor, encoded upstream smeDEF, in its complementary DNA strand. In the present article we present the crystal structure of SmeT and analyze its interactions with its cognate operator. Like other members of the TetR family of transcriptional repressors, SmeT behaves as a dimer and presents some common structural features with other TetR proteins like TtgR, QacR, and TetR. Differing from other TetR proteins for which the structure is available, SmeT turned out to have two extensions at the N and C termini that might be relevant for its function. Besides, SmeT presents the smallest binding pocket so far described in the TetR family of transcriptional repressors, which may correlate with a specific type and range of effectors. In vitro studies revealed that SmeT binds to a 28-bp pseudopalindromic region, forming two complexes. This operator region was found to overlap the promoters of smeT and smeDEF. This finding is consistent with a role for SmeT simultaneously down-regulating smeT and smeDEF transcription, likely by steric hindrance on RNA polymerase binding to DNA. |
| Links |
PubMed PMC2682891 Online version:10.1074/jbc.M809221200 |
| Keywords |
Bacterial Proteins/chemistry; Bacterial Proteins/genetics; Bacterial Proteins/metabolism; Base Sequence; Binding Sites; Crystallography, X-Ray; DNA, Bacterial/metabolism; Drug Resistance, Multiple, Bacterial; Ligands; Models, Molecular; Molecular Sequence Data; Operator Regions, Genetic/genetics; Promoter Regions, Genetic/genetics; Protein Binding; Protein Structure, Secondary; Protein Structure, Tertiary; Repressor Proteins/metabolism; Stenotrophomonas maltophilia/metabolism; Structural Homology, Protein |
| edit table |
Significance
Annotations
| Gene product | Qualifier | GO Term | Evidence Code | with/from | Aspect | Extension | Notes | Status |
|---|---|---|---|---|---|---|---|---|
See also
References
See Help:References for how to manage references in GONUTS.
