Details

Autor(en) / Beteiligte

• Tan, Yong Zi
• Zhang, Lei
• Rodrigues, José
• Zheng, Ruixiang Blake
• Giacometti, Sabrina I.
• Rosário, Ana L.
• Kloss, Brian
• Dandey, Venkata P.
• Wei, Hui
• Brunton, Richard
• Raczkowski, Ashleigh M.
• Athayde, Diogo
• Catalão, Maria João
• Pimentel, Madalena
• Clarke, Oliver B.
• Lowary, Todd L.
• Archer, Margarida
• Niederweis, Michael
• Potter, Clinton S.
• Carragher, Bridget
• Mancia, Filippo

Titel

Cryo-EM Structures and Regulation of Arabinofuranosyltransferase AftD from Mycobacteria

Ist Teil von

• Molecular cell, 2020-05, Vol.78 (4), p.683-699.e11

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2020

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• Mycobacterium tuberculosis causes tuberculosis, a disease that kills over 1 million people each year. Its cell envelope is a common antibiotic target and has a unique structure due, in part, to two lipidated polysaccharides—arabinogalactan and lipoarabinomannan. Arabinofuranosyltransferase D (AftD) is an essential enzyme involved in assembling these glycolipids. We present the 2.9-Å resolution structure of M. abscessus AftD, determined by single-particle cryo-electron microscopy. AftD has a conserved GT-C glycosyltransferase fold and three carbohydrate-binding modules. Glycan array analysis shows that AftD binds complex arabinose glycans. Additionally, AftD is non-covalently complexed with an acyl carrier protein (ACP). 3.4- and 3.5-Å structures of a mutant with impaired ACP binding reveal a conformational change, suggesting that ACP may regulate AftD function. Mutagenesis experiments using a conditional knockout constructed in M. smegmatis confirm the essentiality of the putative active site and the ACP binding for AftD function. [Display omitted] •Cryo-EM structures of mycobacterial arabinofuranosyltransferase D (AftD) were solved•AftD has a conserved GT-C glycosyltransferase fold and binds complex arabinose glycans•Acyl carrier protein (ACP) is complexed to AftD, also endogenously•Impairment of ACP binding alters conformation, suggesting ACP plays a regulatory role Tan et al. present the cryo-EM structures of essential wild-type and mutant mycobacterial arabinofuranosyltransferase D (AftD), revealing the putative active site geometry and carbohydrate-binding modules. Acyl carrier protein (ACP) was tightly associated with AftD. Impairing ACP binding blocks AftD’s active site, suggesting that ACP regulates enzyme function.