1UQT

Trehalose-6-phosphate from E. coli bound with UDP-2-fluoro glucose.

Summary for 1UQT

• Entry DOI: 10.2210/pdb1uqt/pdb
• Related: 1GZ5 1UQU
• Descriptor: ALPHA, ALPHA-TREHALOSE-PHOSPHATE SYNTHASE, URIDINE-5'-DIPHOSPHATE-2-DEOXY-2-FLUORO-ALPHA-D-GLUCOSE (3 entities in total)
• Functional Keywords: synthase, glycosyltransferase, transferase
• Biological source: ESCHERICHIA COLI
• Total number of polymer chains: 2
• Total formula weight: 110630.80

Authors

Gibson, R.P.,Tarling, C.A.,Roberts, S.,Withers, S.G.,Davies, G.J. (deposition date: 2003-10-20, release date: 2003-12-12, Last modification date: 2023-12-13)

Primary citation

Gibson, R.P.,Tarling, C.A.,Roberts, S.,Withers, S.G.,Davies, G.J.
The donor subsite of trehalose-6-phosphate synthase: binary complexes with UDP-glucose and UDP-2-deoxy-2-fluoro-glucose at 2 A resolution.
J. Biol. Chem., 279:1950-1955, 2004

PubMed Abstract: Trehalose is an unusual non-reducing disaccharide that plays a variety of biological roles, from food storage to cellular protection from environmental stresses such as desiccation, pressure, heat-shock, extreme cold, and oxygen radicals. It is also an integral component of the cell-wall glycolipids of mycobacteria. The primary enzymatic route to trehalose first involves the transfer of glucose from a UDP-glucose donor to glucose-6-phosphate to form alpha,alpha-1,1 trehalose-6-phosphate. This reaction, in which the configurations of two glycosidic bonds are set simultaneously, is catalyzed by the glycosyltransferase trehalose-6-phosphate synthase (OtsA), which acts with retention of the anomeric configuration of the UDP-sugar donor. The classification of activated sugar-dependent glycosyltransferases into approximately 70 distinct families based upon amino acid sequence similarities places OtsA in glycosyltransferase family 20 (see afmb.cnrs-mrs.fr/CAZY/). The recent 2.4 A structure of Escherichia coli OtsA revealed a two-domain enzyme with catalysis occurring at the interface of the twin beta/alpha/beta domains. Here we present the 2.0 A structures of the E. coli OtsA in complex with either UDP-Glc or the non-transferable analogue UDP-2-deoxy-2-fluoroglucose. Both complexes unveil the donor subsite interactions, confirming a strong similarity to glycogen phosphorylases, and reveal substantial conformational differences to the previously reported complex with UDP and glucose 6-phosphate. Both the relative orientation of the two domains and substantial (up to 10 A) movements of an N-terminal loop (residues 9-22) characterize the more open "relaxed" conformation of the binary UDP-sugar complexes reported here.

PubMed: 14570926
DOI: 10.1074/jbc.M307643200

Experimental method

X-RAY DIFFRACTION (2 Å)