ISSN:
1745-4514
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Process Engineering, Biotechnology, Nutrition Technology
Notes:
An acid peroxidase isoenzyme (A1) from Brussels sprouts (Brassica oleraceae L.) has been purified while another isoenzyme (A2) has been partially purified. Studies of their properties leading to a potential application in immunoassays as an alternative to horseradish peroxidase were conducted. Isoenzyme A1 was purified 503 fold, through ammonium sulfate and acetone fractionation, and successive chromatography on DEAE-cellulose, Sephadex G-100 and Mono-S (FPLC system) columns. Isoenzyme A1 had a pI of 4.0, a molecular weight of 90 kDa, and contained two identical molecular weight subunits. Preliminary studies indicated a pI of 4.7 for isoenzyme A2. ABTS [2,2′-azino-di-(3-ethyl-benzthiazoline-6-sulfonic acid)] Km values (0.2 mM) for both isoenzymes are 20 times lower than those reported for commercial horseradish peroxidase anionic isoenzymes. Optimum pH for activity of isoenzymes A1 and A2 were 4.3 and 4.5, respectively. Optimum temperature for isoenzyme A1 was 57C, with an activation energy for inactivation of 148.8 kJ/mol.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-4514.1999.tb00029.x
