Crystal structures of wild-type p-hydroxybenzoate hydroxylase complexed with 4-aminobenzoate,2,4-dihydroxybenzoate, and 2-hydroxy-4-aminobenzoate and of the Tyr222Ala mutant complexed with 2-hydroxy-4-aminobenzoate. Evidence for a proton channel and a new binding mode of the flavin ringSchreuder, H.A., Mattevi, A., Obmolova, G., Kalk, K.H., Hol, W.G., van der Bolt, F.J., van Berkel, W.J.
(1994) Biochemistry 33: 10161-10170
- PubMed: 7520279
- Primary Citation of Related Structures:  1PBB, 1PBC, 1PBD
- PubMed Abstract:
- Crystal Structure of the Reduced Form of P-Hydroxybenzoate Hydroxylase Refined at 2.3 Angstroms Resolution
Schreuder, H.A.,Van Der Laan, J.M.,Swarte, M.B.A.,Kalk, K.H.,Hol, W.G.J.,Drenth, J.
(1992) Proteins 14: 178
- Crystallization and Preliminary X-Ray Investigation of P-Hydroxybenzoate Hydroxylase from Pseudomonas Fluorescens
Drenth, J.,Hol, W.G.J.,Wierenga, R.K.
(1975) J.Biol.Chem. 250: 5268
- Molecular Modeling Reveals the Possible Importance of a Carbonyl Oxygen Binding Pocket for the Catalytic Mechanism of P-Hydroxybenzoate Hydroxylase
Schreuder, H.A.,Hol, W.G.J.,Drenth, J.
(1988) J.Biol.Chem. 263: 3131
- The Coenzyme Analogue Adenosine 5-Diphosphoribose Displaces Fad in the Active Site of P-Hydroxybenzoate Hydroxylase. An X-Ray Crystallographic Investigation
Van Der Laan, J.M.,Schreuder, H.A.,Swarte, M.B.A.,Wierenga, R.K.,Kalk, K.H.,Hol, W.G.J.,Drenth, J.
(1989) Biochemistry 28: 7199
- Crystal Structure of the P-Hydroxybenzoate Hydroxylase-Substrate Complex Refined at 1.9 Angstroms Resolution. Analysis of the Enzyme-Substrate and Enzyme-Product Complexes
Schreuder, H.A.,Prick, P.A.J.,Wierenga, R.K.,Vriend, G.,Wilson, K.S.,Hol, W.G.J.,Drenth, J.
(1989) J.Mol.Biol. 208: 679
- Crystal Structure of P-Hydroxybenzoate Hydroxylase Complexed with its Reaction Product 3,4-Dihydroxybenzoate
Schreuder, H.A.,Van Der Laan, J.M.,Hol, W.G.J.,Drenth, J.
(1988) J.Mol.Biol. 199: 637
- Crystal Structure of P-Hydroxybenzoate Hydroxylase
Wierenga, R.K.,De Jong, R.J.,Kalk, K.H.,Hol, W.G.J.,Drenth, J.
(1979) J.Mol.Biol. 131: 55
- The Influence of Purification and Protein Heterogeneity on the Crystallization of P-Hydroxybenzoate Hydroxylase
Van Der Laan, J.M.,Swarte, M.B.A.,Groendijk, H.,Hol, W.G.J.,Drenth, J.
(1989) Eur.J.Biochem. 179: 715
- Comparison of the Three-Dimensional Protein and Nucleotide Structure of the Fad-Binding Domain of P-Hydroxybenzoate Hydroxylase with the Fad-as Well as Nadph-Binding Domains of Glutathione Reductase
Wierenga, R.K.,Drenth, J.,Schulz, G.E.
(1983) J.Mol.Biol. 167: 725
- Analysis of the Active Site of the Flavoprotein P-Hydroxybenzoate Hydroxylase and Some Ideas with Respect to its Reaction Mechanism
Schreuder, H.A.,Hol, W.G.J.,Drenth, J.
(1989) Biochemistry 29: 3101
The crystal structures of wild-type p-hydroxybenzoate hydroxylase from Pseudomonas fluorescens, complexed with the substrate analogues 4-aminobenzoate, 2,4-dihydroxybenzoate, and 2-hydroxy-4-aminobenzoate have been determined at 2.3-, 2.5-, and 2.8-A ...
The crystal structures of wild-type p-hydroxybenzoate hydroxylase from Pseudomonas fluorescens, complexed with the substrate analogues 4-aminobenzoate, 2,4-dihydroxybenzoate, and 2-hydroxy-4-aminobenzoate have been determined at 2.3-, 2.5-, and 2.8-A resolution, respectively. In addition, the crystal structure of a Tyr222Ala mutant, complexed with 2-hydroxy-4-aminobenzoate, has been determined at 2.7-A resolution. The structures have been refined to R factors between 14.5% and 15.8% for data between 8.0 A and the high-resolution limit. The differences between these complexes and the wild-type enzyme-substrate complex are all concentrated in the active site region. Binding of substrate analogues bearing a 4-amino group (4-aminobenzoate and 2-hydroxy-4-aminobenzoate) leads to binding of a water molecule next to the active site Tyr385. As a result, a continuous hydrogen-bonding network is present between the 4-amino group of the substrate analogue and the side chain of His72. It is likely that this hydrogen-bonding network is transiently present during normal catalysis, where it may or may not function as a proton channel assisting the deprotonation of the 4-hydroxyl group of the normal substrate upon binding to the active site. Binding of substrate analogues bearing a hydroxyl group at the 2-position (2,4-dihydroxybenzoate and 2-hydroxy-4-aminobenzoate) leads to displacement of the flavin ring from the active site. The flavin is no longer in the active site (the "in" conformation) but is in the cleft leading to the active site instead (the "out" conformation). It is proposed that movement of the FAD out of the active site may provide an entrance for the substrate to enter the active site and an exit for the product to leave.
Bioson Research Institute, University of Groningen, The Netherlands.