title: Distinct structural features of the peroxide response regulator from group A Streptococcus drive DNA binding.
abstract: Group A streptococcus (GAS, Streptococcus pyogenes) is a strict human pathogen that causes severe, invasive diseases. GAS does not produce catalase, but has an ability to resist killing by reactive oxygen species (ROS) through novel mechanisms. The peroxide response regulator (PerR), a member of ferric uptake regulator (Fur) family, plays a key role for GAS to cope with oxidative stress by regulating the expression of multiple genes. Our previous studies have found that expression of an iron-binding protein, Dpr, is under the direct control of PerR. To elucidate the molecular interactions of PerR with its cognate promoter, we have carried out structural studies on PerR and PerR-DNA complex. By combining crystallography and small-angle X-ray scattering (SAXS), we confirmed that the determined PerR crystal structure reflects its conformation in solution. Through mutagenesis and biochemical analysis, we have identified DNA-binding residues suggesting that PerR binds to the dpr promoter at the per box through a winged-helix motif. Furthermore, we have performed SAXS analysis and resolved the molecular architecture of PerR-DNA complex, in which two 30 bp DNA fragments wrap around two PerR homodimers by interacting with the adjacent positively-charged winged-helix motifs. Overall, we provide structural insights into molecular recognition of DNA by PerR and define the hollow structural arrangement of PerR-30bpDNA complex, which displays a unique topology distinct from currently proposed DNA-binding models for Fur family regulators.
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Chang Sheng-Huei
authors.initials: CS
authors.lastname: Lin
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Shi-Yu
authors.initials: SY
authors.lastname: Chao
authors.affiliation: Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America.
authors.forename: Michal
authors.initials: M
authors.lastname: Hammel
authors.affiliation: Molecular Biology Consortium, Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America.
authors.forename: Jay C
authors.initials: JC
authors.lastname: Nix
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan ; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Hsiao-Ling
authors.initials: HL
authors.lastname: Tseng
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan ; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Tsou
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Chun-Hsien
authors.initials: CH
authors.lastname: Fei
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Huo-Sheng
authors.initials: HS
authors.lastname: Chiou
authors.affiliation: National Synchrotron Radiation Research Center, Hsinchu, Taiwan.
authors.forename: U-Ser
authors.initials: US
authors.lastname: Jeng
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan ; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Yee-Shin
authors.initials: YS
authors.lastname: Lin
authors.affiliation: Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Woei-Jer
authors.initials: WJ
authors.lastname: Chuang
authors.affiliation: Molecular Biology Consortium, Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America ; Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Jiunn-Jong
authors.initials: JJ
authors.lastname: Wu
authors.affiliation: Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan ; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Shuying
authors.initials: S
authors.lastname: Wang
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D003461:Crystallography; D004269:DNA, Bacterial / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics / Q000502:physiology*; D008958:Models, Molecular; D016296:Mutagenesis; D011487:Protein Conformation; D017382:Reactive Oxygen Species / Q000378:metabolism; D012097:Repressor Proteins / Q000737:chemistry* / Q000378:metabolism*; D053838:Scattering, Small Angle; D013297:Streptococcus pyogenes / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; C414750:Dpr protein, Streptococcus; D017382:Reactive Oxygen Species; D012097:Repressor Proteins; C122138:peroxide repressor proteins