Triosephosphate isomerases in Italian ryegrass ( Lolium multiflorum ): characterization and susceptibility to herbicides.
The effect of treatments with four herbicides and a safener on the activity of triosephosphate isomerase (TPI) extracted from shoots of Italian ryegrass was investigated. It was found that atrazine and fluorodifen, herbicides which interfere with photosynthesis, caused a decrease in measured enzyme activity. In addition, the in vitro effect of oxidized glutathione (GSSG), a compound produced in situations of oxidative stress, on TPI activity was investigated. It was shown that GSSG was a strong inhibitor of enzyme activity, at low concentrations in a dose-time-dependent manner. The enzyme extracts were submitted to chromatographic purifications and to two-dimensional electrophoresis. Some spots had molecular masses ranging between 20 and 30 kDa and were characterized and identified by LC-ESI-MS/MS as TPIs. The mass spectrometry also made it possible to identify the presence of cysteine residues that could be subjected to S-glutathionylation, which regulate the enzyme activity.
Del Buono
Daniele
D
Dipartimento di Scienze Agrarie e Ambientali, Universita degli Studi di Perugia, Borgo XX Giugno 72, 06121 Perugia, Italy. delbuono@unipg.it
Prinsi
Bhakti
B
Espen
Luca
L
Scarponi
Luciano
L
D001280:Atrazine / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D019803:Glutathione Disulfide / Q000494:pharmacology; D055768:Halogenated Diphenyl Ethers / Q000494:pharmacology; D006540:Herbicides / Q000494:pharmacology*; D008129:Lolium / Q000187:drug effects* / Q000201:enzymology*; D018520:Plant Shoots / Q000201:enzymology; D014305:Triose-Phosphate Isomerase / Q000037:antagonists & inhibitors* / Q000302:isolation & purification / Q000378:metabolism*
D004791:Enzyme Inhibitors; D055768:Halogenated Diphenyl Ethers; D006540:Herbicides; D014305:Triose-Phosphate Isomerase; C010457:fluorodifen; D001280:Atrazine; D019803:Glutathione Disulfide