Asymmetric biosynthesis of intermediates of anti-HIV drugs

Human immunodeficiency virus (HIV) infection is the fifth most common cause of death and many new HIV infections occur every year. The prevalence of HIV also seriously affects the quality of a patient’s life. More than forty anti-HIV drugs have been put into clinical uses, many of which are chiral molecules with multiple stereogenic centers, for example abacavir, lamivudine, zidovudine, stavudine, tenofovir, atazanavir. However, the chemical synthesis of these chiral intermediates have the disadvantages of low enantiomeric purity and complex synthetic steps. The benefits of asymmetric biosynthesis of chiral drugs include high enantiomeric excess (e.e.), good product selectivity, mild reaction conditions, and less side effects. The biosynthesis of the chiral intermediates of these anti-HIV drugs is thus particularly important. Herein, we review the different sources of enzymes and microbial cells for the asymmetric biosynthesis of the above chiral anti-HIV drug intermediates. We also review recent biotechnology progress in engineering these enzymes and microbial cells with improved biocatalytic activities, including enzyme and cell immobilization, surface display of enzymes, and directed evolution of enzymes. These biotechnology processes enable the efficient biosynthesis of these chiral intermediates, facilitating the industrial production of anti-HIV drugs with reduced costs.