4D48

Crystal Structure of glucose-1-phosphate uridylyltransferase GalU from Erwinia amylovora.

Summary for 4D48

• Entry DOI: 10.2210/pdb4d48/pdb
• Related: 4D47
• Descriptor: GLUCOSE-1-PHOSPHATE URIDYLYLTRANSFERASE (2 entities in total)
• Functional Keywords: transferase, amylovoran biosynthesis, udp-glucose, fire blight
• Biological source: ERWINIA AMYLOVORA
• Total number of polymer chains: 2
• Total formula weight: 65845.95

Authors

Toccafondi, M.,Wuerges, J.,Cianci, M.,Benini, S. (deposition date: 2014-10-27, release date: 2016-01-20, Last modification date: 2023-12-20)

Primary citation

Benini, S.,Toccafondi, M.,Rejzek, M.,Musiani, F.,Wagstaff, B.A.,Wuerges, J.,Cianci, M.,Field, R.A.
Glucose-1-phosphate uridylyltransferase from Erwinia amylovora: Activity, structure and substrate specificity.
Biochim. Biophys. Acta, 1865:1348-1357, 2017

PubMed Abstract: Erwinia amylovora, a Gram-negative plant pathogen, is the causal agent of Fire Blight, a contagious necrotic disease affecting plants belonging to the Rosaceae family, including apple and pear. E. amylovora is highly virulent and capable of rapid dissemination in orchards; effective control methods are still lacking. One of its most important pathogenicity factors is the exopolysaccharide amylovoran. Amylovoran is a branched polymer made by the repetition of units mainly composed of galactose, with some residues of glucose, glucuronic acid and pyruvate. E. amylovora glucose-1-phosphate uridylyltransferase (UDP-glucose pyrophosphorylase, EC 2.7.7.9) has a key role in amylovoran biosynthesis. This enzyme catalyses the production of UDP-glucose from glucose-1-phosphate and UTP, which the epimerase GalE converts into UDP-galactose, the main building block of amylovoran. We determined EaGalU kinetic parameters and substrate specificity with a range of sugar 1-phosphates. At time point 120min the enzyme catalysed conversion of the sugar 1-phosphate into the corresponding UDP-sugar reached 74% for N-acetyl-α-d-glucosamine 1-phosphate, 28% for α-d-galactose 1-phosphate, 0% for α-d-galactosamine 1-phosphate, 100% for α-d-xylose 1-phosphate, 100% for α-d-glucosamine 1-phosphate, 70% for α-d-mannose 1-phosphate, and 0% for α-d-galacturonic acid 1-phosphate. To explain our results we obtained the crystal structure of EaGalU and augmented our study by docking the different sugar 1-phosphates into EaGalU active site, providing both reliable models for substrate binding and enzyme specificity, and a rationale that explains the different activity of EaGalU on the sugar 1-phosphates used. These data demonstrate EaGalU potential as a biocatalyst for biotechnological purposes, as an alternative to the enzyme from Escherichia coli, besides playing an important role in E. amylovora pathogenicity.

PubMed: 28844747
DOI: 10.1016/j.bbapap.2017.08.015

Experimental method

X-RAY DIFFRACTION (2.46 Å)