A malachite green-based assay to assess glucan phosphatase activity

Anal Biochem. 2013 Apr 1;435(1):54-6. doi: 10.1016/j.ab.2012.10.044. Epub 2012 Nov 29.


With the recent discovery of a unique class of dual-specificity phosphatases that dephosphorylate glucans, we report an in vitro assay tailored for the detection of phosphatase activity against phosphorylated glucans. We demonstrate that, in contrast to a general phosphatase assay using a synthetic substrate, only phosphatases that possess glucan phosphatase activity liberate phosphate from the phosphorylated glucan amylopectin using the described assay. This assay is simple and cost-effective, providing reproducible results that clearly establish the presence or absence of glucan phosphatase activity. The assay described will be a useful tool in characterizing emerging members of the glucan phosphatase family.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amylopectin / metabolism*
  • Animals
  • Arabidopsis / enzymology
  • Dual-Specificity Phosphatases / metabolism*
  • Enzyme Assays / economics
  • Enzyme Assays / methods*
  • Glycogen / metabolism
  • Humans
  • Phosphorylation
  • Rabbits
  • Rosaniline Dyes / analysis*
  • Rosaniline Dyes / metabolism
  • Starch / metabolism
  • Substrate Specificity


  • Rosaniline Dyes
  • malachite green
  • Starch
  • Glycogen
  • Amylopectin
  • Dual-Specificity Phosphatases