PDBsum entry 2amg

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protein metals links
Hydrolase PDB id
Protein chain
415 a.a. *
_CA ×2
Waters ×178
* Residue conservation analysis
PDB id:
Name: Hydrolase
Title: Structure of hydrolase (glycosidase)
Structure: 1,4-alpha-d-glucan maltotetrahydrolase. Chain: a. Ec:
Source: Pseudomonas stutzeri. Organism_taxid: 316
2.00Å     R-factor:   0.178    
Authors: Y.Morishita,K.Hasegawa,Y.Matsuura,M.Kubota,S.Sakai,Y.Katsube
Key ref:
Y.Morishita et al. (1997). Crystal structure of a maltotetraose-forming exo-amylase from Pseudomonas stutzeri. J Mol Biol, 267, 661-672. PubMed id: 9126844 DOI: 10.1006/jmbi.1996.0887
23-Dec-96     Release date:   01-Apr-97    
Supersedes: 1amg
Go to PROCHECK summary

Protein chain
Pfam   ArchSchema ?
P13507  (AMT4_PSEST) -  Glucan 1,4-alpha-maltotetraohydrolase
548 a.a.
415 a.a.*
Key:    PfamA domain  PfamB domain  Secondary structure  CATH domain
* PDB and UniProt seqs differ at 1 residue position (black cross)

 Enzyme reactions 
   Enzyme class: E.C.  - Glucan 1,4-alpha-maltotetraohydrolase.
[IntEnz]   [ExPASy]   [KEGG]   [BRENDA]
      Reaction: Hydrolysis of 1,4-alpha-D-glucosidic linkages in amylaceous polysaccharides so as to remove successive maltotetraose residues from the non-reducing chain ends.
 Gene Ontology (GO) functional annotation 
  GO annot!
  Biological process     carbohydrate metabolic process   1 term 
  Biochemical function     catalytic activity     2 terms  


DOI no: 10.1006/jmbi.1996.0887 J Mol Biol 267:661-672 (1997)
PubMed id: 9126844  
Crystal structure of a maltotetraose-forming exo-amylase from Pseudomonas stutzeri.
Y.Morishita, K.Hasegawa, Y.Matsuura, Y.Katsube, M.Kubota, S.Sakai.
The three-dimensional structure of an exo-type alpha-amylase from Pseudomonas stutzeri which degrades starch from its non-reducing end to produce maltotetraose has been determined by X-ray structure analysis. The catalytic domain of this enzyme (G4-2), whose structure was determined, is a product of spontaneous limited proteolysis in culture broth. It has 429 amino acid residues and a molecular mass of 47,200, and crystallizes in ammonium sulfate solution at pH 7.5. The structure was elucidated by the multiple isomorphous replacement method and refined at 2.0 A resolution, resulting in a final R-factor of 0.178 for significant reflections with a root-mean-square deviation from ideality in bond distances of 0.013 A. The polypeptide chain of this molecule folds into three domains; the first with a (beta/alpha)8 barrel structure, the second with an excursed part from the first one, and the third with five-stranded antiparallel beta-sheets. The active cleft is formed on the C-terminal side of the beta-sheets in the (beta/alpha)8 barrel as in the known endo-type alpha-amylases. A histidine side-chain nitrogen ND1 is coordinated to one of the bound calcium ion. The recognition site of the non-reducing end of the amylose that determines exo-wise degradation is presumed to be at one end of this cleft where there is a disordered loop consisting of the 66th to 72nd residues, and a loop carrying an aspartic acid (Asp160). These structural features may be responsible for the binding of the non-reducing end of the substrate amylose.
  Selected figure(s)  
Figure 5.
Figure 5. Stereo plots of the coordination around the calcium sites: (a) calcium site 1, WAT designates a liganded water molecule WAT553; (b) calcium site 2.
Figure 8.
Figure 8. Stereo pair of a section of the MIR-map at 2.5 Å resolution superimposed on the rnal model in the region of the β-sheets in the (β/α)[8] barrel, at residues Ile19 to Phe23 and Pro329 to Tyr332.
  The above figures are reprinted by permission from Elsevier: J Mol Biol (1997, 267, 661-672) copyright 1997.  
  Figures were selected by an automated process.  

Literature references that cite this PDB file's key reference

  PubMed id Reference
15583388 M.Momma, and Z.Fujimoto (2004).
Expression, crystallization and preliminary X-ray crystallographic studies of Klebsiella pneumoniae maltohexaose-producing alpha-amylase.
  Acta Crystallogr D Biol Crystallogr, 60, 2352-2354.  
14501113 J.Koepke, E.I.Scharff, C.Lücke, H.Rüterjans, and G.Fritzsch (2003).
Statistical analysis of crystallographic data obtained from squid ganglion DFPase at 0.85 A resolution.
  Acta Crystallogr D Biol Crystallogr, 59, 1744-1754.
PDB code: 1pjx
12581203 S.Janecek, B.Svensson, and E.A.MacGregor (2003).
Relation between domain evolution, specificity, and taxonomy of the alpha-amylase family members containing a C-terminal starch-binding domain.
  Eur J Biochem, 270, 635-645.  
12423336 H.Mori, K.S.Bak-Jensen, and B.Svensson (2002).
Barley alpha-amylase Met53 situated at the high-affinity subsite -2 belongs to a substrate binding motif in the beta-->alpha loop 2 of the catalytic (beta/alpha)8-barrel and is critical for activity and substrate specificity.
  Eur J Biochem, 269, 5377-5390.  
11257505 E.A.MacGregor, S.Janecek, and B.Svensson (2001).
Relationship of sequence and structure to specificity in the alpha-amylase family of enzymes.
  Biochim Biophys Acta, 1546, 1.  
11737209 H.Mori, K.S.Bak-Jensen, T.E.Gottschalk, M.S.Motawia, I.Damager, B.L.Møller, and B.Svensson (2001).
Modulation of activity and substrate binding modes by mutation of single and double subsites +1/+2 and -5/-6 of barley alpha-amylase 1.
  Eur J Biochem, 268, 6545-6558.  
11272837 Y.Mezaki, Y.Katsuya, M.Kubota, and Y.Matsuura (2001).
Crystallization and structural analysis of intact maltotetraose-forming exo-amylase from Pseudomonas stutzeri.
  Biosci Biotechnol Biochem, 65, 222-225.
PDB code: 1gcy
9558324 A.K.Schmidt, S.Cottaz, H.Driguez, and G.E.Schulz (1998).
Structure of cyclodextrin glycosyltransferase complexed with a derivative of its main product beta-cyclodextrin.
  Biochemistry, 37, 5909-5915.
PDB code: 3cgt
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