Purification of chloroperoxidase from Musa paradisiaca stem juice. Issue 2 (19th December 2012)

• Record Type: Journal Article
• Authors: Yadav, Pratibha; Yadav, Meera; Yadav, K. D. S.; Sharma, J. K.; Singh, V. K.
• Is Part Of: International journal of chemical kinetics. Volume 45:Issue 2(2013:Feb.)
• Page Start: 92
• Page End: 100
• Publication Date: 2012-12-19
• Subjects: Chemical kinetics -- Periodicals; 541.394
• DOI: 10.1002/kin.20746
• Languages: English
• ISSNs: 0538-8066

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Chloroperoxidase from M<italic>usa paradisiaca</italic> stem juice has been purified to homogeneity using a concentration obtained by ultrafiltration and anion exchange chromatography on diethylaminoethyl (DEAE) cellulose. The purified enzyme gave a single protein band in SDS‐PAGE analysis corresponding to molecular mass of 43 kDa. The native PAGE analysis result has also given a single protein band, confirming the purity of the enzyme. The purified enzyme was chlorinated and brominated with monochlorodimedone, the substrate used for measuring the halogenating activity of chloroperoxidases. The <italic>K</italic><sub>m</sub> and <italic>k</italic><sub>cat</sub> values using monochlorodimedone as the substrate were 20 μM and 1.64 s<sup>−1</sup>, respectively, giving a <italic>k</italic><sub>cat</sub>/<italic>K</italic><sub>m</sub> value of 8.2 × 10<sup>4</sup> M<sup>−1</sup> s<sup>−1</sup>. The pH and temperature optima of the chlorinating activity were 3.0 and 25°C, respectively. The <italic>K</italic><sub>m</sub> values for the peroxidase activity using pyragallol and H<sub>2</sub>O<sub>2</sub> as the variable substrates were 89 and 120 μM, respectively. The pH and temperature optima of the peroxidase activity using pyrogalllol as the substrate were the same as the pH and temperature optima of the halogenating activity. The peroxidase activity of the enzyme is competitively inhibited by sodium azide, indicating that it is a hemeperoxidase different from nonheme peroxidases. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 45: 92–100, 2013</p> </abstract>