5Z5I

Crystal structure of a thermostable glycoside hydrolase family 43 {beta}-1,4-xylosidase from Geobacillus thermoleovorans IT-08 in complex with L-arabinose and D-xylose

Summary for 5Z5I

• Entry DOI: 10.2210/pdb5z5i/pdb
• Descriptor: Beta-xylosidase, CALCIUM ION, beta-L-arabinofuranose, ... (6 entities in total)
• Functional Keywords: xylanolytic, gh43, oligosaccharide, saccharification, hydrolase
• Biological source: Geobacillus thermoleovorans (Bacillus thermoleovorans)
• Total number of polymer chains: 1
• Total formula weight: 62243.92

Authors

Rohman, A.,van Oosterwijk, N.,Puspaningsih, N.N.T.,Dijkstra, B.W. (deposition date: 2018-01-18, release date: 2018-04-25, Last modification date: 2023-11-22)

Primary citation

Rohman, A.,van Oosterwijk, N.,Puspaningsih, N.N.T.,Dijkstra, B.W.
Structural basis of product inhibition by arabinose and xylose of the thermostable GH43 beta-1,4-xylosidase from Geobacillus thermoleovorans IT-08.
PLoS ONE, 13:e0196358-e0196358, 2018

PubMed Abstract: Complete degradation of the xylan backbone of hemicellulosic plant cell walls requires the synergistic action of endo-xylanases and β-1,4-xylosidases. While endo-xylanases produce xylooligosaccharides from xylan, β-1,4-xylosidases degrade the xylooligosaccharides into xylose monomers. The glycoside hydrolase family 43 β-1,4-xylosidase from Geobacillus thermoleovorans IT-08 is a promising, heat stable catalyst for the saccharification of hemicellulosic material into simple fermentable sugars, but it is competitively inhibited by its products arabinose and xylose. As a first step to help overcome this problem, we elucidated crystal structures of the enzyme in the unliganded form and with bound products, at 1.7-2.0 Å resolution. The structures are very similar to those of other enzymes belonging to glycoside hydrolase family 43. Unexpectedly, the monosaccharides are bound in very different ways. Arabinose preferentially binds in subsite -1, while xylose exclusively interacts with subsite +1. These structures and sugar binding preferences suggest ways for improving the catalytic performance of the enzyme by rational mutational design.

PubMed: 29698436
DOI: 10.1371/journal.pone.0196358

Experimental method

X-RAY DIFFRACTION (1.7 Å)