3ZX5

The 3-dimensional structure of MpgP from Thermus thermophilus HB27, covalently bound to vanadate and in complex with alpha- mannosylglycerate and magnesium

Summary for 3ZX5

• Entry DOI: 10.2210/pdb3zx5/pdb
• Related: 3ZTW 3ZTY 3ZU6 3ZUP 3ZW7 3ZWD 3ZWK 3ZX4
• Descriptor: MANNOSYL-3-PHOSPHOGLYCERATE PHOSPHATASE, MAGNESIUM ION, oxido(dioxo)vanadium, ... (5 entities in total)
• Functional Keywords: hydrolase, haloalkanoid acid dehalogenase-like phosphatase, had-like phosphatase, crystallographic snapshot
• Biological source: THERMUS THERMOPHILUS
• Total number of polymer chains: 2
• Total formula weight: 57221.49

Authors

Goncalves, S.,Esteves, A.M.,Santos, H.,Borges, N.,Matias, P.M. (deposition date: 2011-08-07, release date: 2011-10-19, Last modification date: 2024-11-20)

Primary citation

Goncalves, S.,Esteves, A.M.,Santos, H.,Borges, N.,Matias, P.M.
The Three-Dimensional Structure of Mannosyl-3-Phosphoglycerate Phosphatase from Thermus Thermophilus Hb27: A New Member of the Haloalkanoic Acid Dehalogenase Superfamily.
Biochemistry, 50:9551-, 2011

PubMed Abstract: 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, α-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.

PubMed: 21961705
DOI: 10.1021/BI201171H

Experimental method

X-RAY DIFFRACTION (1.81 Å)