Crystal structures of substrate and inhibitor complexes of ribose 5-phosphate isomerase A from Vibrio vulnificus YJ016.
Ribose-5-phosphate isomerase A (RpiA) plays an important role in interconverting between ribose-5-phosphate (R5P) and ribulose-5-phosphate in the pentose phosphate pathway and the Calvin cycle. We have determined the crystal structures of the open form RpiA from Vibrio vulnificus YJ106 (VvRpiA) in complex with the R5P and the closed form with arabinose-5-phosphate (A5P) in parallel with the apo VvRpiA at 2.0 A resolution. VvRpiA is highly similar to Eschericihia coliRpiA, and the VvRpiA-R5P complex strongly resembles the E. coli RpiA-A5P complex. Interestingly, unlike the E. coli RpiA-A5P complex, the position of A5P in the VvRpiA-A5P complex reveals a different position than the R5P binding mode. VvRpiA-A5P has a sugar ring inside the binding pocket and a phosphate group outside the binding pocket: By contrast, the sugar ring of A5P interacts with the Asp4, Lys7, Ser30, Asp118, and Lys121 residues; the phosphate group of A5P interacts with two water molecules, W51 and W82.
Kim
Tae Gyun
TG
Department of Chemistry, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Kwon
Taek Hun
TH
Min
Kyoungin
K
Dong
Mi-Sook
MS
Park
Young In
YI
Ban
Changill
C
D019747:Aldose-Ketose Isomerases / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry*; D055503:Protein Multimerization; D017433:Protein Structure, Secondary; D013379:Substrate Specificity; D041261:Vibrio vulnificus / Q000201:enzymology
D004791:Enzyme Inhibitors; D019747:Aldose-Ketose Isomerases; C022548:ribosephosphate isomerase