5U20

X-ray structure of the WlaRG aminotransferase from Campylobacter jejuni, internal PLP-aldimine

Summary for 5U20

• Entry DOI: 10.2210/pdb5u20/pdb
• Related: 5U21 5U23 5U24 5u1z
• Descriptor: Putative aminotransferase, SODIUM ION, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: aminotransferase lipooligosaccharide pyridoxal 5'-phosphate, transferase
• Biological source: Campylobacter jejuni
• Total number of polymer chains: 4
• Total formula weight: 177234.09

Authors

Thoden, J.B.,Holden, H.M.,Dow, G.T.,Gilbert, M. (deposition date: 2016-11-29, release date: 2017-01-11, Last modification date: 2023-11-15)

Primary citation

Dow, G.T.,Gilbert, M.,Thoden, J.B.,Holden, H.M.
Structural investigation on WlaRG from Campylobacter jejuni: A sugar aminotransferase.
Protein Sci., 26:586-599, 2017

PubMed Abstract: Campylobacter jejuni is a Gram-negative bacterium that represents a leading cause of human gastroenteritis worldwide. Of particular concern is the link between C. jejuni infections and the subsequent development of Guillain-Barré syndrome, an acquired autoimmune disorder leading to paralysis. All Gram-negative bacteria contain complex glycoconjugates anchored to their outer membranes, but in most strains of C. jejuni, this lipoglycan lacks the O-antigen repeating units. Recent mass spectrometry analyses indicate that the C. jejuni 81116 (Penner serotype HS:6) lipoglycan contains two dideoxyhexosamine residues, and enzymological assay data show that this bacterial strain can synthesize both dTDP-3-acetamido-3,6-dideoxy-d-glucose and dTDP-3-acetamido-3,6-dideoxy-d-galactose. The focus of this investigation is on WlaRG from C. jejuni, which plays a key role in the production of these unusual sugars by functioning as a pyridoxal 5'-phosphate dependent aminotransferase. Here, we describe the first three-dimensional structures of the enzyme in various complexes determined to resolutions of 1.7 Å or higher. Of particular significance are the external aldimine structures of WlaRG solved in the presence of either dTDP-3-amino-3,6-dideoxy-d-galactose or dTDP-3-amino-3,6-dideoxy-d-glucose. These models highlight the manner in which WlaRG can accommodate sugars with differing stereochemistries about their C-4' carbon positions. In addition, we present a corrected structure of WbpE, a related sugar aminotransferase from Pseudomonas aeruginosa, solved to 1.3 Å resolution.

PubMed: 28028852
DOI: 10.1002/pro.3109

Experimental method

X-RAY DIFFRACTION (1.5 Å)