Premium
STUDIES OF VANDADIUM‐BROMOPEROXIDASE USING SURFACE AND CORTICAL PROTOPLASTS OF MACROCYSTIS PYRIEFERA (PHAEOPHYTA) 1
Author(s) -
Butler Alison,
Soedjak Helena S.,
PolneFuller Meiram,
Gibor Aharon,
Boyen Catherine,
Kloareg Bernard
Publication year - 1990
Publication title -
journal of phycology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.85
H-Index - 127
eISSN - 1529-8817
pISSN - 0022-3646
DOI - 10.1111/j.0022-3646.1990.00589.x
Subject(s) - phloroglucinol , protoplast , biology , macrocystis pyrifera , halogenation , hydrogen peroxide , tris , bromide , vanadium , peroxidase , biochemistry , nuclear chemistry , botany , algae , chemistry , organic chemistry , enzyme
Aqueous Tri‐SO 4 buffer (pH 8.3) extracts of cortical and surface protoplasts of Macrocystis pyrifera (L.) C. Ag. Catalyzed the bromination of monochlorodimedone (2‐chloro‐5, 5‐dimethyl‐1, 3‐dimedone, MCD) in the presence of hydrogen peroxide and bromide. The apparent bromo‐peroxidase activity as measured by the bromination of MCD was inhibited by the presence of endogenous compounds which are probably polyphenolics compounds (i.e. polymers of phloroglucinol) or other inhibitors. The bromoperoxidase activity of the protoplast extracts increased substantially when the extracts were washed extensively with Tris‐SO 4 buffer (pH 8.3) by ultrafiltration. The bromoperoxidase activity of both surface and cortical protoplast extracts was dependent on the presence of vanadium, indicating that the bromoperoxidase present in cortical and surface cells of M. pyrifera is vanadium‐bromoperoxidase. Halogenated compounds constitute one of the most significant classes of marine natural products. Since bromoperoxidases are assumed to be involved in the biosynthesis of these compounds, elucidation of the location of BrPO with in the algal tissue is important.