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Cryo-EM structure of arabinosyltransferase EmbB from Mycobacterium smegmatis.

ABSTRACT: Arabinosyltransferase B (EmbB) belongs to a family of membrane-bound glycosyltransferases that build the lipidated polysaccharides of the mycobacterial cell envelope, and are targets of anti-tuberculosis drug ethambutol. We present the 3.3 Å resolution single-particle cryo-electron microscopy structure of Mycobacterium smegmatis EmbB, providing insights on substrate binding and reaction mechanism. Mutations that confer ethambutol resistance map mostly around the putative active site, suggesting this to be the location of drug binding.

SUBMITTER: Tan YZ

PROVIDER: S-EPMC7341804 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Cryo-EM structure of arabinosyltransferase EmbB from Mycobacterium smegmatis.

Tan Yong Zi YZ Rodrigues José J Keener James E JE Zheng Ruixiang Blake RB Brunton Richard R Kloss Brian B Giacometti Sabrina I SI Rosário Ana L AL Zhang Lei L Niederweis Michael M Clarke Oliver B OB Lowary Todd L TL Marty Michael T MT Archer Margarida M Potter Clinton S CS Carragher Bridget B Mancia Filippo F

Nature communications 20200707 1

Arabinosyltransferase B (EmbB) belongs to a family of membrane-bound glycosyltransferases that build the lipidated polysaccharides of the mycobacterial cell envelope, and are targets of anti-tuberculosis drug ethambutol. We present the 3.3 Å resolution single-particle cryo-electron microscopy structure of Mycobacterium smegmatis EmbB, providing insights on substrate binding and reaction mechanism. Mutations that confer ethambutol resistance map mostly around the putative active site, suggesting ...[more]

PMID: 32636380

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