Article Per Year (5 Year)
p-Index From 2021 - 2026
0
P-Index
This Author published in this journals
All Journal Jurnal Matematika & Sains
Harold M. Goff
Department of Chemistry, University of Iowa, Iowa
Mathematics

Published : 1 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 1 Documents
Search

 1 
Evaluation of the Ethylene Effect on Well Defined Copper Enzymes Megawati Santoso; Harold M. Goff
Jurnal Matematika & Sains Vol 11, No 1 (2006)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

An indirect approach in studying ethylene binding sites of copper enzymes was carried out since ethylene pleitropic effect in plants and the general affinity of Cu(I) complexes for ethylene suggest a possibility of ethylene binding to various copper enzymes. For this purpose, superoxide dismutase (SOD) and tyrosinase were evaluated using two different methods. H-NMR spectra of three different conditions of SOD (native SOD; reduced SOD; and reduced SOD in the presence of ethylene) were acquired at 25 °C. Activity of mushroom tyrosinase was monitored in the absence of ethylene by evaluating the formation of dopachrome at 475 nm. Three other assay systems were constructed the same way as the control, except one of the reagents (enzyme, DL-DOPA, or sodium phosphate buffer) was each saturated with ethylene prior to mixing all of reagents. Both systems behaved unsatisfactorily for the purpose of evaluation. The coordinated ethylene proton-NMR signal was obscured by the broad HOD signal, due to the partial oxidation of Cu(I) SOD by trace oxygen. Nonetheless, the tyrosinase assay results demonstrated that displacement of oxygen in the assay system by ethylene did not account for the loss of activity. The observed ethylene effect on tyrosinase activity, however, was minimal, since ethylene could produce threshold physiological response at concentration of 6.5 x 10-9 M.
Co-Authors Megawati Santoso