1WZZ

Structure of endo-beta-1,4-glucanase CMCax from Acetobacter xylinum

Summary for 1WZZ

• Entry DOI: 10.2210/pdb1wzz/pdb
• Descriptor: Probable endoglucanase, SULFATE ION (3 entities in total)
• Functional Keywords: glycoside hydrolase family 8 (gh-8), (alpha/alpha)6 barrel, structural genomics, structural genomics consortium for research on gene expression system, sgcges, hydrolase
• Biological source: Gluconacetobacter xylinus
• Cellular location: Secreted: P37696
• Total number of polymer chains: 1
• Total formula weight: 37576.92

Authors

Yasutake, Y.,Kawano, S.,Tajima, K.,Yao, M.,Satoh, Y.,Munekata, M.,Tanaka, I.,Structural Genomics Consortium (SGC) (deposition date: 2005-03-10, release date: 2006-03-14, Last modification date: 2011-07-13)

Primary citation

Yasutake, Y.,Kawano, S.,Tajima, K.,Yao, M.,Satoh, Y.,Munekata, M.,Tanaka, I.
Structural characterization of the Acetobacter xylinum endo-beta-1,4-glucanase CMCax required for cellulose biosynthesis.
Proteins, 64:1069-1077, 2006

PubMed Abstract: Previous studies have demonstrated that endoglucanase is required for cellulose biosynthesis both in bacteria and plants. However, it has yet to be elucidated how the endoglucanases function in the mechanism of cellulose biosynthesis. Here we describe the crystal structure of the cellulose biosynthesis-related endo-beta-1,47-glucanase (CMCax; EC 3.2.1.4) from the cellulose-producing Gramnegative bacterium, Acetobacter xylinum (= Gluconacetobacter xylinus), determined at 1.65-A resolution. CMCax falls into the glycoside hydrolase family 8 (GH-8), and the structure showed that the overall fold of the CMCax is similar to those of other glycoside hydrolases belonging to GH-8. Structure comparison with Clostridium thermocellum CelA, the best characterized GH-8 endoglucanase, revealed that sugar recognition subsite +3 is completely missing in CMCax. The absence of the subsite +3 leads to significant broadness of the cleft at the cellooligosaccharide reducing-end side. CMCax is known to be a secreted enzyme and is present in the culture medium. However, electron microscopic analysis using immunostaining clearly demonstrated that a portion of CMCax is localized to the cell surface, suggesting a link with other known membrane-anchored endoglucanases that are required for cellulose biosynthesis.

PubMed: 16804941
DOI: 10.1002/prot.21052

Experimental method

X-RAY DIFFRACTION (1.65 Å)