Arabinosyltransferase C (EmbC) (EmbC)

EmbC is a membrane-bound arabinosyltransferase essential for the biosynthesis of lipoarabinomannan (LAM) in Mycobacterium tuberculosis (UniProt: P9WNJ9). It belongs to the Emb protein family, which includes EmbA and EmbB, all of which are critical for constructing the complex mycobacterial cell envelope (Zhang et al., 2020, Science). While EmbA and EmbB are primarily responsible for the synthesis of arabinogalactan, EmbC specifically catalyzes the assembly of the arabinan domain of LAM, a key lipoglycan that modulates the host immune response during infection (Goude et al., 2009, Molecular Microbiology). The first-line antitubercular drug ethambutol targets EmbC (alongside EmbA and EmbB), inhibiting its enzymatic activity and disrupting cell wall integrity (PubChem: CID 14052). Resistance to ethambutol often arises from mutations within the embCAB operon, making EmbC a significant focus for structural biology and the development of next-generation antibiotics.

Other names

EmbCArabinosyltransferase CMycobacterium tuberculosis EmbCProbable arabinosyltransferase C

Inhibition of arabinosyltransferase activity, which prevents the polymerization of D-arabinofuranose units into the arabinan core of lipoarabinomannan (LAM), leading to cell wall instability.