Advances in protein lipoylation pathways in bacteria

Abstract:

Lipoic acid is a derivative of octanoic acid with two sulfur atoms at carbon atoms 6 and 8. The strong antioxidant activity of lipoic acid makes it have a good application prospect in the fields of health food, cosmetics and medicine. Lipoic acid as an important cofactor is required for several key enzymes complexes, like α-ketoacid dehydrogenase, and it also involves in energy generation and intermediate metabolisms. The protein lipoylation pathways have been well studied in the model organism Escherichia coli, including the lipoic acid de novo synthetic pathway dependent on LipB-LipA and the lipoic acid salvage pathway dependent on LplA. However, the lipoylation pathways in different bacteria show a highly diversity. The GcvH protein in certain bacteria also participates in protein lipoylation eventhough the related enzymes are different. In this review, we comprehensively discussed the current research progress on lipoic acid dependent multiple enzyme complexes, the lipoyl domain, GcvH proteins, as well as the protein lipoylation pathways in differen bacteria, aiming to provide theoretical support for further understanding the protein lipoylation in bacteria, developing the targeted antibacterial drugs, and efficient lipoic acid production with biological methods.

Key words:lipoic acid;lipoic acid de novo synthetic pathway;lipoic acid salvage pathway