5BRQ

Crystal structure of Bacillus licheniformis trehalose-6-phosphate hydrolase (TreA)

Summary for 5BRQ

• Entry DOI: 10.2210/pdb5brq/pdb
• Related: 5BRP
• Descriptor: Glycoside Hydrolase Family 13, MAGNESIUM ION (3 entities in total)
• Functional Keywords: trehalose-6-phosphate hydrolase, tim barrel, gh13 family, hydrolase
• Biological source: Bacillus licheniformis ATCC 14580 = DSM 13
• Total number of polymer chains: 4
• Total formula weight: 266666.47

Authors

Hsiao, C.-D.,Lin, M.-G. (deposition date: 2015-06-01, release date: 2016-03-02, Last modification date: 2023-11-08)

Primary citation

Lin, M.-G.,Chi, M.-C.,Naveen, V.,Li, Y.-C.,Lin, L.-L.,Hsiao, C.-D.
Bacillus licheniformis trehalose-6-phosphate hydrolase structures suggest keys to substrate specificity
Acta Crystallogr D Struct Biol, 72:59-70, 2016

PubMed Abstract: Trehalose-6-phosphate hydrolase (TreA) belongs to glycoside hydrolase family 13 (GH13) and catalyzes the hydrolysis of trehalose 6-phosphate (T6P) to yield glucose and glucose 6-phosphate. The products of this reaction can be further metabolized by the energy-generating glycolytic pathway. Here, crystal structures of Bacillus licheniformis TreA (BlTreA) and its R201Q mutant complexed with p-nitrophenyl-α-D-glucopyranoside (R201Q-pPNG) are presented at 2.0 and 2.05 Å resolution, respectively. The overall structure of BlTreA is similar to those of other GH13 family enzymes. However, detailed structural comparisons revealed that the catalytic site of BlTreA contains a long loop that adopts a different conformation from those of other GH13 family members. Unlike the homologous regions of Bacillus cereus oligo-1,6-glucosidase (BcOgl) and Erwinia rhapontici isomaltulose synthase (NX-5), the surface potential of the BlTreA active site exhibits a largely positive charge contributed by the four basic residues His281, His282, Lys284 and Lys292. Mutation of these residues resulted in significant decreases in the enzymatic activity of BlTreA. Strikingly, the (281)HHLK(284) motif and Lys292 play critical roles in substrate discrimination by BlTreA.

PubMed: 26894535
DOI: 10.1107/S2059798315020756

Experimental method

X-RAY DIFFRACTION (2.003 Å)