3zx4 | pdb_00003zx4

THE 3-DIMENSIONAL STRUCTURE OF MPGP FROM THERMUS THERMOPHILUS HB27, IN COMPLEX WITH THE ALPHA-MANNOSYLGLYCERATE,ORTHOPHOSPHATE AND MAGNESIUM

spinqualitylabelsall models 3zx4, resolution 1.74Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3zx4 is a 2 chain structure with sequence from Thermus thermophilus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: 2M8, MG, PO4 Related: 3zwk, 3zup, 3zty, 3ztw, 3zu6, 3zw7, 3zwd, 3zx5 Activity: Mannosyl-3-phosphoglycerate phosphatase, with EC number 3.1.3.70 Resources: FirstGlance, OCA, RCSB, PDBsum Publication Abstract from PubMed Mannosyl-3-phosphoglycerate phosphatase (MpgP) is a key mediator in the physiological response to thermal and osmotic stresses, catalyzing the hydrolysis of mannosyl-3-phosphoglycerate (MPG) to the final product, alpha-mannosylglycerate. MpgP is a metal-dependent haloalcanoic acid dehalogenase-like (HAD-like) phosphatase, preserving the catalytic motifs I-IV of the HAD core domain, and classified as a Cof-type MPGP (HAD-IIB-MPGP family; SCOP [117505]) on the basis of its C2B cap insertion module. Herein, the crystallographic structures of Thermus thermophilus HB27 MpgP in its apo form and in complex with substrates, substrate analogues, and inhibitors are reported. Two distinct enzyme conformations, open and closed, are catalytically relevant. Apo-MpgP is primarily found in the open state, while holo-MpgP, in complex with the reaction products, is found in the closed state. Enzyme activation entails a structural rearrangement of motifs I and IV with concomitant binding of the cocatalytic Mg(2+) ion. The closure motion of the C2B domain is subsequently triggered by the anchoring of the phosphoryl group to the cocatalytic metal center, and by Arg167 fixing the mannosyl moiety inside the catalytic pocket. The results led to the proposal that in T. thermophilus HB27 MpgP the phosphoryl transfer employs a concerted D(N)S(N) mechanism with assistance of proton transfer from the general acid Asp8, forming a short-lived PO(3)(-) intermediate that is attacked by a nucleophilic water molecule. These results provide new insights into a possible continuum of phosphoryl transfer mechanisms, ranging between those purely associative and dissociative, as well as a picture of the main mechanistic aspects of phosphoryl monoester transfer catalysis, common to other members of the HAD superfamily. Three-Dimensional Structure of Mannosyl-3-phosphoglycerate Phosphatase from Thermus thermophilus HB27: A New Member of the Haloalcanoic Acid Dehalogenase Superfamily.,Goncalves S, Esteves AM, Santos H, Borges N, Matias PM Biochemistry. 2011 Oct 13. PMID:21961705 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

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