Arabinosyl transferase enzyme complex (null)

The Arabinosyl transferase enzyme complex refers to a family of integral membrane glycosyltransferases, including proteins like EmbA, EmbB, EmbC, and AftA, which are essential for the assembly of the arabinan component of arabinogalactan and lipoarabinomannan in the mycobacterial cell wall[1][2][3][4][9]. These enzymes catalyze the transfer of arabinose residues from decaprenylphosphoryl-arabinose (DPA) donors to polysaccharide acceptors via specific glycosidic linkages, supporting the structural integrity and function of the cell envelope in *Mycobacterium tuberculosis*[1][4]. They are validated therapeutic targets, as inhibition by drugs like ethambutol impairs cell wall construction and leads to bactericidal effects[1][3][6]. The term "Arabinosyl transferase enzyme complex" sometimes refers specifically to an *enzyme dimer* (e.g., EmbB~2~-AcpM~2~) or broadly to the functional set of related enzymes[1][2]. The best-characterized clinical target is EmbB, especially for ethambutol, but other family members (EmbA, EmbC, AftA) play non-redundant, essential roles in cell wall biosynthesis in mycobacteria[1][2][3][5][6].

Other names

Emb protein complexEmbA-EmbB-EmbC complexarabinofuranosyltransferase complexAG arabinosyltransferasearabinofuranosyltransferase (family includes EmbA, EmbB, EmbC, AftA, AftB)

Ethambutol inhibits these arabinosyltransferases by binding to the same site as their natural substrates and blocking arabinose transfer, thus disrupting cell wall synthesis and compromising bacterial viability[1][3][5][6].