3DDB

Crystal structure of the catalytic domain of Botulinum neurotoxin serotype a with a substrate analog peptide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Substrate binding mode and its implication on drug design for botulinum neurotoxin A

Kumaran, D.Rawat, R.Ahmed, S.A.Swaminathan, S.

(2008) PLoS Pathog 4: e1000165-e1000165

  • DOI: 10.1371/journal.ppat.1000165
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The seven antigenically distinct serotypes of Clostridium botulinum neurotoxins, the causative agents of botulism, block the neurotransmitter release by specifically cleaving one of the three SNARE proteins and induce flaccid paralysis. The Centers f ...

    The seven antigenically distinct serotypes of Clostridium botulinum neurotoxins, the causative agents of botulism, block the neurotransmitter release by specifically cleaving one of the three SNARE proteins and induce flaccid paralysis. The Centers for Disease Control and Prevention (CDC) has declared them as Category A biowarfare agents. The most potent among them, botulinum neurotoxin type A (BoNT/A), cleaves its substrate synaptosome-associated protein of 25 kDa (SNAP-25). An efficient drug for botulism can be developed only with the knowledge of interactions between the substrate and enzyme at the active site. Here, we report the crystal structures of the catalytic domain of BoNT/A with its uncleavable SNAP-25 peptide (197)QRATKM(202) and its variant (197)RRATKM(202) to 1.5 A and 1.6 A, respectively. This is the first time the structure of an uncleavable substrate bound to an active botulinum neurotoxin is reported and it has helped in unequivocally defining S1 to S5' sites. These substrate peptides make interactions with the enzyme predominantly by the residues from 160, 200, 250 and 370 loops. Most notably, the amino nitrogen and carbonyl oxygen of P1 residue (Gln197) chelate the zinc ion and replace the nucleophilic water. The P1'-Arg198, occupies the S1' site formed by Arg363, Thr220, Asp370, Thr215, Ile161, Phe163 and Phe194. The S2' subsite is formed by Arg363, Asn368 and Asp370, while S3' subsite is formed by Tyr251, Leu256, Val258, Tyr366, Phe369 and Asn388. P4'-Lys201 makes hydrogen bond with Gln162. P5'-Met202 binds in the hydrophobic pocket formed by the residues from the 250 and 200 loop. Knowledge of interactions between the enzyme and substrate peptide from these complex structures should form the basis for design of potent inhibitors for this neurotoxin.


    Organizational Affiliation

    Biology Department, Brookhaven National Laboratory, Upton, New York, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Botulinum neurotoxin A light chainA430Clostridium botulinumMutation(s): 0 
Gene Names: botA
EC: 3.4.24.69
Find proteins for P0DPI1 (Clostridium botulinum (strain Hall / ATCC 3502 / NCTC 13319 / Type A))
Explore P0DPI1 
Go to UniProtKB:  P0DPI1
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
  • Find similar proteins by: Sequence   |   Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Synaptosomal-associated protein 25B7N/AMutation(s): 0 
Find proteins for P60880 (Homo sapiens)
Explore P60880 
Go to UniProtKB:  P60880
NIH Common Fund Data Resources
PHAROS  P60880
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
ZN
Query on ZN

Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 50.871α = 90
b = 66.581β = 98.34
c = 65.062γ = 90
Software Package:
Software NamePurpose
CNSrefinement
CBASSdata collection
HKL-2000data reduction
HKL-2000data scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-09-16
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance