A high-throughput colorimetric assay to characterize the enzyme kinetic and cellular activity of spermidine/spermine N1-acetyltransferase 1

Anal Biochem. 2010 Dec 15;407(2):226-32. doi: 10.1016/j.ab.2010.07.036. Epub 2010 Aug 6.


Spermidine/spermine N(1)-acetyltransferase 1 (SSAT1) is a key enzyme that catalyzes the catabolism of polyamines. SSAT1 is a very important enzyme because it not only maintains the homeostasis of polyamines but also is involved in many physiological and pathological events. As such, a rapid assay of SSAT1 activity is valuable in drug screening and clinical diagnostics. Here, we report a novel colorimetric assay for monitoring SSAT1 activity in zebrafish (zSSAT1). In comparison with the available SSAT1 assays, this new method is cost-effective and simple. The optimal zSSAT1 activity was obtained below 55°C in a mild alkaline environment. The K(m) values of zSSAT1 for spermidine and spermine are 55 and 182 μM, respectively, whereas putrescine is not a good substrate for zSSAT1. In addition to enzyme kinetic studies, the colorimetric assay was also used to detect the cellular activity of SSAT1. Thus, the current method is a reliable assay for determining SSAT1 activity with many potential applications in medical biology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetyltransferases / chemistry
  • Acetyltransferases / genetics
  • Acetyltransferases / metabolism*
  • Animals
  • Colorimetry / methods*
  • Enzyme Assays / methods*
  • High-Throughput Screening Assays / methods*
  • Kinetics
  • Polyamines / metabolism
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Zebrafish
  • Zebrafish Proteins / chemistry
  • Zebrafish Proteins / genetics
  • Zebrafish Proteins / metabolism*


  • Polyamines
  • Recombinant Proteins
  • Zebrafish Proteins
  • Acetyltransferases
  • diamine N-acetyltransferase