title: Extensive mutagenesis experiments corroborate a structural model for the DNA deaminase domain of APOBEC3G.
abstract: APOBEC3G is a single-strand DNA cytosine deaminase capable of blocking retrovirus and retrotransposon replication. APOBEC3G has two conserved zinc-coordinating motifs but only one is required for catalysis. Here, deletion analyses revealed that the minimal catalytic domain consists of residues 198-384. Size exclusion assays indicated that this protein is monomeric. Many (31/69) alanine substitution derivatives of APOBEC3G198-384 retained significant to full levels of activity. These data corroborated an APOBEC2-based structural model for the catalytic domain of APOBEC3G indicating that most non-essential residues are solvent accessible and most essential residues cluster within the protein core.
authors.affiliation: University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics, Minneapolis, MN 55455, United States. chen0775@umn.edu
authors.forename: Kuan-Ming
authors.initials: KM
authors.lastname: Chen
authors.forename: Natalia
authors.initials: N
authors.lastname: Martemyanova
authors.forename: Yongjian
authors.initials: Y
authors.lastname: Lu
authors.forename: Keisuke
authors.initials: K
authors.lastname: Shindo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsuo
authors.forename: Reuben S
authors.initials: RS
authors.lastname: Harris
mesh_terms: D000071480:APOBEC-3G Deaminase; D020816:Amino Acid Motifs; D002850:Chromatography, Gel; D003564:Cytidine Deaminase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004247:DNA / Q000378:metabolism*; D003641:Deamination; D015870:Gene Expression; D006801:Humans; D008958:Models, Molecular; D016296:Mutagenesis; D010641:Phenotype; D017434:Protein Structure, Tertiary; D040681:Structural Homology, Protein
chemical_list: D004247:DNA; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase