1NAG

CREVICE-FORMING MUTANTS IN THE RIGID CORE OF BOVINE PANCREATIC TRYPSIN INHIBITOR: CRYSTAL STRUCTURES OF F22A, Y23A, N43G, AND F45A

• PDB DOI: https://doi.org/10.2210/pdb1NAG/pdb

• Classification: SERINE PROTEASE INHIBITOR
• Organism(s): Bos taurus
• Mutation(s): No 


• Deposited: 1992-08-18 Released: 1993-10-31 
• Deposition Author(s): Danishefsky, A.T., Wlodawer, A., Kim, K.-S., Tao, F., Woodward, C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Work: 0.163 
• R-Value Observed: 0.163 

Literature

Crevice-forming mutants in the rigid core of bovine pancreatic trypsin inhibitor: crystal structures of F22A, Y23A, N43G, and F45A.

Danishefsky, A.T., Housset, D., Kim, K.S., Tao, F., Fuchs, J., Woodward, C., Wlodawer, A.

(1993) Protein Sci 2: 577-587

• PubMed: 8518731 
• DOI: https://doi.org/10.1002/pro.5560020409
• Primary Citation of Related Structures:  
  1BPT, 1BTI, 1FAN, 1NAG


• PubMed Abstract: 
  

  Crystal structures of four mutants of bovine pancreatic trypsin inhibitor (F22A, Y23A, N43G, and F45A), engineered to alter their stability properties, have been determined. The mutated residues, which are highly conserved among Kunitz-type inhibitors, are located in the rigid core of the molecule. Replacement of the partially buried bulky residues of the wild-type protein with smaller residues resulted in crevices open to the exterior of the molecule. The overall three-dimensional structure of these mutants is very similar to that of the wild-type protein and only small rearrangements are observed among the atoms lining the crevices.

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Organizational Affiliation: 

Macromolecular Structure Laboratory, NCI-Frederick Cancer Research and Development Center, ABL, Basic Research Program, Maryland 21702.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 6.57 kDa 
• Atom Count: 509 
• Modelled Residue Count: 56 
• Deposited Residue Count: 58 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
BOVINE PANCREATIC TRYPSIN INHIBITOR	A	58	Bos taurus	Mutation(s): 0
UniProt
Find proteins for P00974 (Bos taurus) Explore P00974  Go to UniProtKB:  P00974

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PO4	B [auth A]	PHOSPHATE ION O4 P NBIIXXVUZAFLBC-UHFFFAOYSA-K

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Work: 0.163 
• R-Value Observed: 0.163 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 55.72	α = 90
b = 37.98	β = 90
c = 23.79	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
PROLSQ	refinement
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1993-10-31 
Deposition Author(s): Danishefsky, A.T., Wlodawer, A., Kim, K.-S., Tao, F., Woodward, C.

Revision History  

• Version 1.0: 1993-10-31
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2019-07-17
  Changes: Data collection, Other, Refinement description
• Version 1.4: 2019-08-14
  Changes: Data collection, Refinement description
• Version 1.5: 2024-10-30
  Changes: Data collection, Database references, Derived calculations, Structure summary