6PQK

Cryogenic crystal structure of barnase A43C/S80C bound to barstar C40A/S59C/A67C/C82A

• PDB DOI: https://doi.org/10.2210/pdb6PQK/pdb

• Classification: RNA BINDING PROTEIN
• Organism(s): Bacillus amyloliquefaciens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2019-07-09 Released: 2020-07-15 
• Deposition Author(s): Caro, J.A., Djanto, V., Wand, A.J.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.160 
• R-Value Work: 0.138 
• R-Value Observed: 0.138 

Literature

Targeting conformational entropy to modulate binding affinity

Caro, J.A., Djanto, V., Wand, A.J.

To be published.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration, isothermal titration calorimetry

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 50.35 kDa 
• Atom Count: 4,014 
• Modelled Residue Count: 394 
• Deposited Residue Count: 436 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Ribonuclease	A, B [auth C]	128	Bacillus amyloliquefaciens	Mutation(s): 2  EC: 3.1.27
UniProt
Find proteins for P00648 (Bacillus amyloliquefaciens) Explore P00648  Go to UniProtKB:  P00648

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Barstar	C [auth B], D	90	Bacillus amyloliquefaciens	Mutation(s): 4
UniProt
Find proteins for P11540 (Bacillus amyloliquefaciens) Explore P11540  Go to UniProtKB:  P11540

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PO4	E [auth A], J [auth B], K [auth D], L [auth D]	PHOSPHATE ION O4 P NBIIXXVUZAFLBC-UHFFFAOYSA-K
EDO	F [auth A], G [auth A], H [auth C], I [auth C]	1,2-ETHANEDIOL C2 H6 O2 LYCAIKOWRPUZTN-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.20 Å
• R-Value Free: 0.160 
• R-Value Work: 0.138 
• R-Value Observed: 0.138 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 36.704	α = 90
b = 68.404	β = 90
c = 166.723	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	data scaling
PHASER	phasing
PDB_EXTRACT	data extraction

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2020-07-15 
Deposition Author(s): Caro, J.A., Djanto, V., Wand, A.J.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	R01GM102447

Revision History  

• Version 1.0: 2020-07-15
  Type: Initial release