5U6M
Crystal structure of UDP-glucosyltransferase, UGT74F2, with UDP and salicylic acid
Summary for 5U6M
| Entry DOI | 10.2210/pdb5u6m/pdb |
| Related | 5U6N 5U6S |
| Descriptor | UDP-glycosyltransferase 74F2, beta-D-glucopyranose, URIDINE-5'-DIPHOSPHATE, ... (5 entities in total) |
| Functional Keywords | udp-glucosyltransferase, salicylic acid, salicylic acid glucoside, salicylic acid ester, transferase |
| Biological source | Arabidopsis thaliana (Mouse-ear cress) |
| Total number of polymer chains | 2 |
| Total formula weight | 103088.12 |
| Authors | George Thompson, A.M.,Iancu, C.V.,Dean, J.V.,Choe, J. (deposition date: 2016-12-08, release date: 2017-05-03, Last modification date: 2020-07-29) |
| Primary citation | George Thompson, A.M.,Iancu, C.V.,Neet, K.E.,Dean, J.V.,Choe, J.Y. Differences in salicylic acid glucose conjugations by UGT74F1 and UGT74F2 from Arabidopsis thaliana. Sci Rep, 7:46629-46629, 2017 Cited by PubMed Abstract: Salicylic acid (SA) is a signaling molecule utilized by plants in response to various stresses. Through conjugation with small organic molecules such as glucose, an inactive form of SA is generated which can be transported into and stored in plant vacuoles. In the model organism Arabidopsis thaliana, SA glucose conjugates are formed by two homologous enzymes (UGT74F1 and UGT74F2) that transfer glucose from UDP-glucose to SA. Despite being 77% identical and with conserved active site residues, these enzymes catalyze the formation of different products: UGT74F1 forms salicylic acid glucoside (SAG), while UGT74F2 forms primarily salicylic acid glucose ester (SGE). The position of the glucose on the aglycone determines how SA is stored, further metabolized, and contributes to a defense response. We determined the crystal structures of the UGT74F2 wild-type and T15S mutant enzymes, in different substrate/product complexes. On the basis of the crystal structures and the effect on enzyme activity of mutations in the SA binding site, we propose the catalytic mechanism of SGE and SAG formation and that SA binds to the active site in two conformations, with each enzyme selecting a certain binding mode of SA. Additionally, we show that two threonines are key determinants of product specificity. PubMed: 28425481DOI: 10.1038/srep46629 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.568 Å) |
Structure validation
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