L-aspartate 1-decarboxylase (PanD)

L-aspartate 1-decarboxylase (PanD) is a vital metabolic enzyme in bacteria, including Mycobacterium tuberculosis, that catalyzes the decarboxylation of L-aspartate to form beta-alanine (UniProt P9WNS5). This enzymatic step is the rate-limiting stage in the biosynthesis of pantothenate (vitamin B5), which serves as the essential precursor for Coenzyme A (CoA) (Zhang et al., 2013, Nature Communications). CoA is a mandatory cofactor for the fatty acid synthase (FAS) complexes responsible for the production of mycolic acids, which are critical components of the mycobacterial cell wall. PanD is recognized as the primary therapeutic target for pyrazinamide (PZA), a frontline drug used in the treatment of tuberculosis (Gopal et al., 2016, Nature Communications). PZA acts as a prodrug that is converted into pyrazinoic acid (POA) by bacterial amidases; POA then binds to PanD and inhibits its activity (PubMed). The resulting depletion of CoA pools halts fatty acid synthesis and disrupts metabolic homeostasis, leading to bacterial cell death, especially in non-replicating persistent populations. Because the pantothenate biosynthetic pathway is absent in humans, PanD represents a highly selective target for antimicrobial intervention (PubChem).

Other names

Aspartate 1-decarboxylaseADCPanDL-aspartate alpha-decarboxylase

Inhibition of L-aspartate 1-decarboxylase prevents the synthesis of beta-alanine, leading to the depletion of pantothenate and Coenzyme A, which ultimately disrupts fatty acid synthesis and mycobacterial cell wall assembly.