Carbonyl Reductase 1 (CBR1)

Carbonyl reductase is one of several monomeric, NADPH-dependent oxidoreductases having wide specificity for carbonyl compounds. This enzyme is widely distributed in human tissues. Another carbonyl reductase gene, CRB3, lies close to this gene on chromosome 21q. CBR1 metabolizes many toxic environmental quinones and pharmacological relevant substrates such as the anticancer doxorubicin.Up-to-date two non-synonymous polymorphisms on CBR1 have been identified. The CBR1 V88I polymorphism encodes for a valine-to-isoleucin substitution at position 88 of the aminoacid chain. In vitro studies with recombinant proteins indicate that the CBR1 V88 isoform has a higher Vmax towards the substrates menadione (vitamin K3) and daunorubicin.