title: TcaR-ssDNA complex crystal structure reveals new DNA binding mechanism of the MarR family proteins.
abstract: The teicoplanin-associated locus regulator (TcaR) regulates gene expression of proteins on the intercellular adhesion (ica) locus involved in staphylococci poly-N-acetylglucosamine biosynthesis. The absence of TcaR increases poly-N-acetylglucosamine production and promotes biofilm formation. Until recently, the mechanism of multiple antibiotic resistance regulator family protein members, such as TcaR, was restricted to binding double-stranded DNA. However, we recently found that TcaR strongly interacts with single-stranded DNA, which is a new role for this family of proteins. In this study, we report Staphylococcus epidermidis TcaR-single-stranded DNA complex structures. Our model suggests that TcaR and single-stranded DNA form a 61-symmetry polymer composed of TcaR dimers with single-stranded DNA that wraps outside the polymer and 12 nt per TcaR dimer. Single-stranded DNA binding to TcaR involves a large conformational change at the DNA binding lobe. Several point mutations involving the single-stranded DNA binding surface validate interactions between single-stranded DNA and TcaR. Our results extend the novel role of multiple antibiotic resistance regulator family proteins in staphylococci.
authors: Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan, Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan, Core Facilities for Protein Structural Analysis, Academia Sinica, Taipei 11529, Taiwan and Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
authors: Yu-Ming
authors: YM
authors: Chang
authors: Chun-Han
authors: CH
authors: Ho
authors: Cammy K-M
authors: CK
authors: Chen
authors: Manuel
authors: M
authors: Maestre-Reyna
authors: Masatoshi Weiting
authors: MW
authors: Chang-Chien
authors: Andrew H-J
authors: AH
authors: Wang
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D004277:DNA, Single-Stranded / Q000737:chemistry* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D011485:Protein Binding; D013212:Staphylococcus epidermidis
chemical_list: D001426:Bacterial Proteins; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins