The Structure-Function Relationship of Human Bleomycin Hydrolase: Mutation of a Cysteine Protease into a Serine Protease.
Zheng, Y.Z., Cui, J., Wang, Y.L., Huang, S.J., Lin, E.C., Huang, S.C., Rudolf, J.D., Yan, X., Chang, C.Y.(2022) Chembiochem 23: e202200186-e202200186
- PubMed: 35467071 
- DOI: https://doi.org/10.1002/cbic.202200186
- Primary Citation of Related Structures:  
7V5L, 7V5S, 7V5T, 7XF9 - PubMed Abstract: 
Human bleomycin hydrolase (hBH) catalyzes deamidation of the anticancer drug bleomycins (BLM). This enzyme is involved in BLM detoxification and drug resistance. Herein, we report the putative BLM-binding site and catalytic mechanism of hBH. The crystal structures and biochemical studies suggest that hBH cleaves its C-terminal residue without significant preference for the type of amino acid, and therefore can accordingly accommodate the β-aminoalanine amide moiety of BLM for deamidation. Interestingly, hBH is capable of switching from a cysteine protease to a serine protease that is unable to cleave the secondary amide of hBH C-terminus but reacts with the primary amide of BLMs.
Organizational Affiliation: 
Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan.