1BSI

HUMAN PANCREATIC ALPHA-AMYLASE FROM PICHIA PASTORIS, GLYCOSYLATED PROTEIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Work: 0.184 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Cloning, mutagenesis, and structural analysis of human pancreatic alpha-amylase expressed in Pichia pastoris.

Rydberg, E.H.Sidhu, G.Vo, H.C.Hewitt, J.Cote, H.C.Wang, Y.Numao, S.MacGillivray, R.T.Overall, C.M.Brayer, G.D.Withers, S.G.

(1999) Protein Sci. 8: 635-643

  • DOI: 10.1110/ps.8.3.635

  • PubMed Abstract: 
  • Human pancreatic alpha-amylase (HPA) was expressed in the methylotrophic yeast Pichia pastoris and two mutants (D197A and D197N) of a completely conserved active site carboxylic acid were generated. All recombinant proteins were shown by electrospray ...

    Human pancreatic alpha-amylase (HPA) was expressed in the methylotrophic yeast Pichia pastoris and two mutants (D197A and D197N) of a completely conserved active site carboxylic acid were generated. All recombinant proteins were shown by electrospray ionization mass spectrometry (ESI-MS) to be glycosylated and the site of attachment was shown to be Asn461 by peptide mapping in conjunction with ESI-MS. Treatment of these proteins with endoglycosidase F demonstrated that they contained a single N-linked oligosaccharide and yielded a protein product with a single N-acetyl glucosamine (GlcNAc), which could be crystallized. Solution of the crystal structure to a resolution of 2.0 A confirmed the location of the glycosyl group as Asn461 and showed that the recombinant protein had essentially the same conformation as the native enzyme. The kinetic parameters of the glycosylated and deglycosylated wild-type proteins were the same while the k(cat)/Km values for D197A and D197N were 10(6)-10(7) times lower than the wild-type enzyme. The decreased k(cat)/Km values for the mutants confirm that D197 plays a crucial role in the hydrolytic activity of HPA, presumably as the catalytic nucleophile.


    Organizational Affiliation

    Department of Biochemistry & Molecular Biology, University of British Columbia, Vancouver, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ALPHA-AMYLASE
A
496Homo sapiensGene Names: AMY2A
EC: 3.2.1.1
Find proteins for P04746 (Homo sapiens)
Go to Gene View: AMY2A
Go to UniProtKB:  P04746
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

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Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
CA
Query on CA

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Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
NAG
Query on NAG

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Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
PCA
Query on PCA
A
L-PEPTIDE LINKINGC5 H7 N O3GLU
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Work: 0.184 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 52.910α = 90.00
b = 68.900β = 90.00
c = 131.770γ = 90.00
Software Package:
Software NamePurpose
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-05-18
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance