Extensive mutagenesis experiments corroborate a structural model for the DNA deaminase domain of APOBEC3G.
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.
Chen
Kuan-Ming
KM
University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics, Minneapolis, MN 55455, United States. chen0775@umn.edu
Martemyanova
Natalia
N
Lu
Yongjian
Y
Shindo
Keisuke
K
Matsuo
Hiroshi
H
Harris
Reuben S
RS
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
D004247:DNA; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase