title: Using structural-based protein engineering to modulate the differential inhibition effects of SAUGI on human and HSV uracil DNA glycosylase.
abstract: Uracil-DNA glycosylases (UDGs) are highly conserved proteins that can be found in a wide range of organisms, and are involved in the DNA repair and host defense systems. UDG activity is controlled by various cellular factors, including the uracil-DNA glycosylase inhibitors, which are DNA mimic proteins that prevent the DNA binding sites of UDGs from interacting with their DNA substrate. To date, only three uracil-DNA glycosylase inhibitors, phage UGI, p56, and Staphylococcus aureus SAUGI, have been determined. We show here that SAUGI has differential inhibitory effects on UDGs from human, bacteria, Herpes simplex virus (HSV; human herpesvirus 1) and Epstein-Barr virus (EBV; human herpesvirus 4). Newly determined crystal structures of SAUGI/human UDG and a SAUGI/HSVUDG complex were used to explain the differential binding activities of SAUGI on these two UDGs. Structural-based protein engineering was further used to modulate the inhibitory ability of SAUGI on human UDG and HSVUDG. The results of this work extend our understanding of DNA mimics as well as potentially opening the way for novel therapeutic applications for this kind of protein.
authors.affiliation: Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
authors.forename: Hao-Ching
authors.initials: HC
authors.lastname: Wang
authors.affiliation: Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan.
authors.forename: Chun-Han
authors.initials: CH
authors.lastname: Ho
authors.affiliation: Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan.
authors.forename: Chia-Cheng
authors.initials: CC
authors.lastname: Chou
authors.affiliation: Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan.
authors.forename: Tzu-Ping
authors.initials: TP
authors.lastname: Ko
authors.affiliation: Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
authors.forename: Ming-Fen
authors.initials: MF
authors.lastname: Huang
authors.affiliation: Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
authors.forename: Kai-Cheng
authors.initials: KC
authors.lastname: Hsu
authors.affiliation: Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan Core Facilities for Protein Structural Analysis, Academia Sinica, Taipei 115, Taiwan ahjwang@gate.sinica.edu.tw.
authors.forename: Andrew H-J
authors.initials: AH
authors.lastname: Wang
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D001665:Binding Sites; D018360:Crystallography, X-Ray; D018259:Herpesvirus 1, Human / Q000201:enzymology; D004854:Herpesvirus 4, Human / Q000201:enzymology; D006801:Humans; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011485:Protein Binding; D015202:Protein Engineering; D054730:Protein Interaction Domains and Motifs; D013211:Staphylococcus aureus; D051981:Uracil-DNA Glycosidase / Q000737:chemistry* / Q000235:genetics; D014764:Viral Proteins / Q000737:chemistry* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D014764:Viral Proteins; D051981:Uracil-DNA Glycosidase