Biological Assembly 1  

 3D View: Structure | Electron Density | Validation Report | Ligand Interaction

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 23.56 kDa 
• Atom Count: 1735 
• Modelled Residue Count: 223 
• Deposited Residue Count: 223 
• Unique protein chains: 1

1TX7

Bovine Trypsin complexed with p-amidinophenylmethylphosphinic acid (AMPA)

• DOI: 10.2210/pdb1TX7/pdb

• Classification: HYDROLASE
• Organism(s): Bos taurus
• Mutation(s): No 


• Deposited: 2004-07-02 Released: 2005-09-20 
• Deposition Author(s): Cui, J., Marankan, F., Fu, W., Crich, D., Mesecar, A., Johnson, M.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.75 Å
• R-Value Free: 0.229 
• R-Value Work: 0.183 
• R-Value Observed: 0.183 

Literature

An oxyanion-hole selective serine protease inhibitor in complex with trypsin.

Cui, J., Marankan, F., Fu, W., Crich, D., Mesecar, A., Johnson, M.E.

(2002) Bioorg Med Chem 10: 41-46

• PubMed: 11738605 
• DOI: 10.1016/s0968-0896(01)00259-0
• Primary Citation of Related Structures:  
  1TX7


• PubMed Abstract: 
  

p-amidinophenylmethylphosphinic acid (AMPA) was designed, synthesized and crystallized in complex with trypsin to study interactions with the oxyanion hole at the S1 site. In comparison to benzamidine, AMPA shows improved activity, which the crystal structure demonstrates to result from hydrogen bonds between the negatively charged phosphinic acid group and the catalytic residues at the oxyanion hole.

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Organizational Affiliation: 

Center for Pharmaceutical Biotechnology, College of Pharmacy, University of Illinois at Chicago, 900 S. Ashland Avenue, M/C 870, Chicago, IL 60607-7173, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Trypsinogen	A	223	Bos taurus	Mutation(s): 0  EC: 3.4.21.4
UniProt
Find proteins for P00760 (Bos taurus) Explore P00760  Go to UniProtKB:  P00760

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
4CM (Subject of Investigation/LOI)	C [auth A]	(4-CARBAMIMIDOYLPHENYL)-METHYL-PHOSPHINIC ACID C8 H11 N2 O2 P CVABPMXIKVDCLF-UHFFFAOYSA-N
CA	B [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
4CM	PDBBind:  1TX7	Ki: 2.50e+4 (nM) from 1 assay(s)
	Binding MOAD:  1TX7	Ki: 2.50e+4 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.75 Å
• R-Value Free: 0.229 
• R-Value Work: 0.183 
• R-Value Observed: 0.183 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 54.87	α = 90
b = 58.44	β = 90
c = 67.52	γ = 90

Structure Validation

Ligand Structure Quality Assessment  

Entry History 

Deposition Data

• Deposited Date: 2004-07-02 
• Released Date: 2005-09-20 
Deposition Author(s): Cui, J., Marankan, F., Fu, W., Crich, D., Mesecar, A., Johnson, M.E.

Revision History  

• Version 1.0: 2005-09-20
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-04-04
  Changes: Data collection