Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 33.78 kDa 
• Atom Count: 2549 
• Residue Count: 274 
• Unique protein chains: 1

3HFB

Crystal structure of human tryoptophan hydroxylase type 1 with LP-534193

• DOI: 10.2210/pdb3HFB/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Homo sapiens
• Mutation(s): Yes 


• Deposited: 2009-05-11 Released: 2010-04-21 
• Deposition Author(s): Tari, L.W., Swanson, R.V., Hunter, M.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.92 Å
• R-Value Free: 0.289 
• R-Value Work: 0.214 
• R-Value Observed: 0.218 

Literature

Mechanism of Inhibition of Novel Tryptophan Hydroxylase Inhibitors Revealed by Co-crystal Structures and Kinetic Analysis.

Cianchetta, G., Stouch, T., Yu, W., Shi, Z.C., Tari, L.W., Swanson, R.V., Hunter, M.J., Hoffman, I.D., Liu, Q.

(2010) Curr Chem Genomics 4: 19-26

• PubMed: 20556201 
• DOI: 10.2174/1875397301004010019
• Primary Citation of Related Structures:  
  3HFB, 3HF8


• PubMed Abstract: 
  

Trytophan Hydroxylase Type I (TPH1), most abundantly expressed in the gastrointestinal tract, initiates the synthesis of serotonin by catalyzing hydroxylation of tryptophan in the presence of biopterin and oxygen. We have previously described three series of novel, periphery-specific TPH1 inhibitors that selectively deplete serotonin in the gastrointestinal tract. We have now determined co-crystal structures of TPH1 with three of these inhibitors at high resolution. Analysis of the structural data showed that each of the three inhibitors fills the tryptophan binding pocket of TPH1 without reaching into the binding site of the cofactor pterin, and induces major conformational changes of the enzyme. The enzyme-inhibitor complexes assume a compact conformation that is similar to the one in tryptophan complex. Kinetic analysis showed that all three inhibitors are competitive versus the substrate tryptophan, consistent with the structural data that the compounds occupy the tryptophan binding site. On the other hand, all three inhibitors appear to be uncompetitive versus the cofactor 6-methyltetrahydropterin, which is not only consistent with the structural data but also indicate that the hydroxylation reaction follows an ordered binding mechanism in which a productive complex is formed only if tryptophan binds only after pterin, similar to the kinetic mechanisms of tyrosine and phenylalanine hydroxylase.

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Organizational Affiliation: 

Department of Medicinal Chemistry, Lexicon Pharmaceuticals, Inc., 350 Carter Rd., Princeton, New Jersey, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Tryptophan 5-hydroxylase 1	A	290	Homo sapiens	Mutation(s): 2  Gene Names: TPH1, TPH, TPRH, TRPH EC: 1.14.16.4
Find proteins for P17752 (Homo sapiens) Explore P17752  Go to UniProtKB:  P17752
NIH Common Fund Data Resources
PHAROS  P17752 GTEx  ENSG00000129167

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ML4	A	4-(5-{[(2'-methylbiphenyl-2-yl)methyl]amino}pyrazin-2-yl)-L-phenylalanine C27 H26 N4 O2 LQRILFQFPLOLRC-DEOSSOPVSA-N
FE	A	FE (III) ION Fe VTLYFUHAOXGGBS-UHFFFAOYSA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
ML4	IC50:  40   nM  BindingDB
ML4	Ki :  30   nM  PDBBind
ML4	Ki:  30   nM  Binding MOAD

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.92 Å
• R-Value Free: 0.289 
• R-Value Work: 0.214 
• R-Value Observed: 0.218 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 47.354	α = 90
b = 58.143	β = 96.77
c = 56.625	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2009-05-11 
• Released Date: 2010-04-21 
Deposition Author(s): Tari, L.W., Swanson, R.V., Hunter, M.J.

Revision History 

• Version 1.0: 2010-04-21
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2012-03-28
  Changes: Database references