Assaying Arabidopsis lipase activity.
A low lipase activity from a crude extract of Arabidopsis seedlings was assayed using three sensitive methods (radiolabelled triacylglycerols, commercial resorufin ester and triacylglycerols containing the naturally fluorescent parinaric acid as substrates). The specific activity of the extract was found to be similar using the three methods. However, the plant lipase activity measured using the radioactivity and the fluorescence assays could be abolished by heating the extract, contrary to the apparent activity measured using the commercial colorimetric assay. Unlike the radioactivity assay, the fluorescence assay can be monitored continuously. The parinaric acid-based method is therefore the only one to provide a sensitive, specific and continuous assay.
Beisson
F
F
Laboratoire de Lipolyse Enzymatique (UPR 9025 du CNRS), Institut de Biologie Structurale et Microbiologie, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
Arondel
V
V
Verger
R
R
D017360:Arabidopsis / Q000201:enzymology*; D002151:Calorimetry / Q000379:methods; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D005456:Fluorescent Dyes; D006801:Humans; D008049:Lipase / Q000378:metabolism*; D010078:Oxazines; D010179:Pancreas / Q000201:enzymology; D011865:Radioisotope Dilution Technique; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods; D014280:Triglycerides / Q000378:metabolism
D005231:Fatty Acids, Unsaturated; D005456:Fluorescent Dyes; D010078:Oxazines; D014280:Triglycerides; C014180:resorufin; D008049:Lipase; C013641:parinaric acid