A CBM20 low-affinity starch-binding domain from glucan, water dikinase

FEBS Lett. 2009 Apr 2;583(7):1159-63. doi: 10.1016/j.febslet.2009.02.045. Epub 2009 Mar 9.

Abstract

The family 20 carbohydrate-binding module (CBM20) of the Arabidopsis starch phosphorylator glucan, water dikinase 3 (GWD3) was heterologously produced and its properties were compared to the CBM20 from a fungal glucoamylase (GA). The GWD3 CBM20 has 50-fold lower affinity for cyclodextrins than that from GA. Homology modelling identified possible structural elements responsible for this weak binding of the intracellular CBM20. Differential binding of fluorescein-labelled GWD3 and GA modules to starch granules in vitro was demonstrated by confocal laser scanning microscopy and yellow fluorescent protein-tagged GWD3 CBM20 expressed in tobacco confirmed binding to starch granules in planta.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / cytology
  • Arabidopsis / enzymology*
  • Arabidopsis / genetics
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Aspergillus niger / enzymology
  • Aspergillus niger / genetics
  • Cyclodextrins / chemistry
  • Cytoplasmic Granules / genetics
  • Cytoplasmic Granules / metabolism
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Gene Expression
  • Glucan 1,4-alpha-Glucosidase / genetics
  • Glucan 1,4-alpha-Glucosidase / metabolism
  • Microscopy, Confocal / methods
  • Nicotiana / genetics
  • Phosphotransferases (Paired Acceptors) / genetics
  • Phosphotransferases (Paired Acceptors) / metabolism*
  • Protein Binding / physiology
  • Protein Structure, Tertiary / physiology
  • Starch / genetics
  • Starch / metabolism*
  • Structural Homology, Protein

Substances

  • Arabidopsis Proteins
  • Cyclodextrins
  • Fungal Proteins
  • Starch
  • Phosphotransferases (Paired Acceptors)
  • alpha-glucan, water dikinase, Arabidopsis
  • Glucan 1,4-alpha-Glucosidase