3BLK

Role of aromatic residues in starch binding

• PDB DOI: https://doi.org/10.2210/pdb3BLK/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda
• Mutation(s): Yes 


• Deposited: 2007-12-11 Released: 2008-11-25 
• Deposition Author(s): Ramasubbu, N.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.215 
• R-Value Work: 0.176 
• R-Value Observed: 0.178 

Starting Model: experimental

Literature

Structure-function relationships in human salivary alpha-amylase: role of aromatic residues in a secondary binding site

Ragunath, C., Manuel, S.G.A., Kasinathan, C., Ramasubbu, N.

(2008) Biologia (Bratisl) 63: 1028-1034

• DOI: https://doi.org/10.2478/s11756-008-0163-3

Biological Assembly 1  

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

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 56.74 kDa 
• Atom Count: 4,181 
• Modelled Residue Count: 496 
• Deposited Residue Count: 496 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Alpha-amylase 1	A	496	Homo sapiens	Mutation(s): 1  Gene Names: AMY1A, AMY1 EC: 3.2.1.1
UniProt & NIH Common Fund Data Resources
Find proteins for P0DUB6 (Homo sapiens) Explore P0DUB6  Go to UniProtKB:  P0DUB6
GTEx:  ENSG00000237763

Oligosaccharides

Help

Entity ID: 2
Molecule	Chains	Length	2D Diagram	Glycosylation	3D Interactions
4-amino-4,6-dideoxy-alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose	B, C	2		N/A
Glycosylation Resources
GlyTouCan:  G90989WB GlyCosmos:  G90989WB

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HMC	F [auth A]	5-HYDROXYMETHYL-CHONDURITOL C7 H12 O5 PJPGMULJEYSZBS-VZFHVOOUSA-N
CA	D [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N
CL	E [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
PCA	A	L-PEPTIDE LINKING	C5 H7 N O3		GLN

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.215 
• R-Value Work: 0.176 
• R-Value Observed: 0.178 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 52.282	α = 90
b = 75.046	β = 90
c = 135.013	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
ADSC	data collection
HKL-2000	data reduction
HKL-2000	data scaling
REFMAC	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2008-11-25 
Deposition Author(s): Ramasubbu, N.

Revision History  

• Version 1.0: 2008-11-25
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 2.0: 2019-12-25
  Changes: Data collection, Database references, Derived calculations, Polymer sequence
• Version 3.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Atomic model, Data collection, Derived calculations, Structure summary
• Version 3.1: 2021-10-20
  Changes: Database references, Derived calculations, Structure summary
• Version 3.2: 2023-08-30
  Changes: Data collection, Refinement description
• Version 3.3: 2024-11-20
  Changes: Structure summary