Structural insight into dephosphorylation by trehalose 6‐phosphate phosphatase (OtsB2) from Mycobacterium tuberculosis. Issue 12 (29th August 2016)

• Record Type: Journal Article
• Authors: Shan, Shan; Min, Haowei; Liu, Ting; Jiang, Dunquan; Rao, Zihe
• Is Part Of: FASEB journal. Volume 30:Issue 12(2016)
• Page Start: 3989
• Page End: 3996
• Publication Date: 2016-08-29
• Subjects: crystal structure -- drug discovery -- MtbTPP; Biology -- Periodicals; Biology, Experimental -- Periodicals; 570
• DOI: 10.1096/fj.201600463R
• Languages: English
• ISSNs: 0892-6638

Abstract

ABSTRACT: Trehalose serves as a key structural component in the cell wall of Mycobacterium tuberculosis . M. tuberculosis trehalose‐6‐phosphate phosphatase ( Mtb TPP), an essential enzyme in the trehalose biosynthesis OtsABpathway, catalyzes thedephosphorylationof trehalose‐6‐phosphate (trehalose‐6‐P) togenerate trehalose, and plays a critical role in M. tuberculosis survival‐associated cell wall formation and permeability. Therefore, Mtb TPP (OtsB2) is considered a promising potential target for discovery of antimicrobial drugs. However, the absence of structural information of Mtb TPP restrains our understanding of its underlying catalytic mechanism. Here, we report the high‐resolution crystal structures of apo active Mtb TPP and its trehalose‐6‐P bound complex. The apo structure presents a canonical haloacid dehalogenase superfamily structural fold plus an extra N‐terminal domain. The catalytic center is located in a positively charged cleft between the hydrolase domain and the cap domain, demonstrating a highly conserved substrate binding pocket. The role of residues interacting with the substrate in catalysis were probed by site‐directed mutagenesis. Asp147, Asp149, Asp330, and Asp331 were found to be pivotal for the enzymatic activity of Mtb TPP. The Mtb TPP structures reported here provide insight into a key step in the biosynthesis of trehalose, which would facilitate future development of anti‐TB therapeutics.—Shan, S., Min, H., Liu, T., Jiang, D., Rao, Z. Structural insight into dephosphorylation by trehalose 6‐phosphate phosphatase (OtsB2) from Mycobacterium tuberculosis . FASEB J. 30, 3989–3996 (2016). www.fasebj.org