Back to Search
Start Over
Purification and characterization of tyrosinase from walnut leaves (Juglans regia).
- Source :
-
Phytochemistry [Phytochemistry] 2014 May; Vol. 101, pp. 5-15. Date of Electronic Publication: 2014 Mar 07. - Publication Year :
- 2014
-
Abstract
- Polyphenol oxidase (PPO) is a type-3 copper enzyme catalyzing the oxidation of phenolic compounds to their quinone derivates, which are further converted to melanin, a ubiquitous pigment in living organisms. In this study a plant originated tyrosinase was isolated from walnut leaves (Juglans regia) and biochemically characterized. It was possible to isolate and purify the enzyme by means of an aqueous two-phase extraction method followed by chromatographic purification and identification. Interestingly, the enzyme showed a rather high monophenolase activity considering that the main part of plant PPOs with some exceptions solely possess diphenolase activity. The average molecular mass of 39,047 Da (Asp(101)→Arg(445)) was determined very accurately by high resolution mass spectrometry. This proteolytically activated tyrosinase species was identified as a polyphenol oxidase corresponding to the known jrPPO1 sequence by peptide sequencing applying nanoUHPLC-ESI-MS/MS. The polypeptide backbone with sequence coverage of 96% was determined to start from Asp(101) and not to exceed Arg(445).<br /> (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Subjects :
- Amino Acid Sequence
Chromatography, High Pressure Liquid
Electrophoresis, Polyacrylamide Gel
Molecular Sequence Data
Monophenol Monooxygenase chemistry
Plant Leaves chemistry
Plant Leaves enzymology
Protein Conformation
Spectrophotometry, Ultraviolet
Tandem Mass Spectrometry
Juglans chemistry
Juglans enzymology
Monophenol Monooxygenase isolation & purification
Subjects
Details
- Language :
- English
- ISSN :
- 1873-3700
- Volume :
- 101
- Database :
- MEDLINE
- Journal :
- Phytochemistry
- Publication Type :
- Academic Journal
- Accession number :
- 24613318
- Full Text :
- https://doi.org/10.1016/j.phytochem.2014.02.010