This protein family includes DNA glycosylase AlkZ from Streptomyces sahachiroi (also known as Azi36) and similar proteins predominantly found in bacteria. AlkZ is an enzyme that provides self-resistance from azinomycin B (AZB) toxicity by unhooking interstrand cross- links (ICLs). The crystal structure of AlkZ revealed a C-shaped configuration with three tandem winged helix-turn-helix (wHTH) motifs and a positively charged surface that shows residues of great importance for the enzymatic activity [1].

1: Structure of a DNA glycosylase that unhooks interstrand cross-links. Mullins EA, Warren GM, Bradley NP, Eichman BF; Proc Natl Acad Sci U S A. 2017;114:4400-4405. PMID:28396405

2: Escherichia coli YcaQ is a DNA glycosylase that unhooks DNA interstrand crosslinks. Bradley NP, Washburn LA, Christov PP, Watanabe CMH, Eichman BF; Nucleic Acids Res. 2020;48:7005-7017. PMID:32409837