1PBK

HOMOLOGOUS DOMAIN OF HUMAN FKBP25

• PDB DOI: https://doi.org/10.2210/pdb1PBK/pdb

• Classification: ISOMERASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1995-09-01 Released: 1996-10-14 
• Deposition Author(s): Liang, J., Hung, D.T., Schreiber, S.L., Clardy, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.243 
• R-Value Work: 0.185 
• R-Value Observed: 0.185 

Literature

Structure of the human 25 kDa FK506 binding protein complexed with rapamycin.

Liang, J., Hung, D.T., Schreiber, S.L., Clardy, J.

(1996) J Am Chem Soc 118: 1231-1232

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 13.87 kDa 
• Atom Count: 1,028 
• Modelled Residue Count: 116 
• Deposited Residue Count: 116 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
FKBP25	A	116	Homo sapiens	Mutation(s): 0  Gene Names: HUMAN HIPPOCAMPAL CDNA LIBRARY EC: 5.2.1.8
UniProt & NIH Common Fund Data Resources
Find proteins for Q00688 (Homo sapiens) Explore Q00688  Go to UniProtKB:  Q00688
PHAROS:  Q00688 GTEx:  ENSG00000100442

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
RAP	B [auth A]	RAPAMYCIN IMMUNOSUPPRESSANT DRUG C51 H79 N O13 QFJCIRLUMZQUOT-HPLJOQBZSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
RAP	PDBBind:  1PBK	Ki: 0.9 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.243 
• R-Value Work: 0.185 
• R-Value Observed: 0.185 
• Space Group: P 4₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 86	α = 90
b = 86	β = 90
c = 55.6	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
DENZO	data reduction
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1996-10-14 
Deposition Author(s): Liang, J., Hung, D.T., Schreiber, S.L., Clardy, J.

Revision History  

• Version 1.0: 1996-10-14
  Type: Initial release
  
• Version 1.1: 2008-03-03
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-14
  Changes: Data collection, Database references, Derived calculations, Other