TY - JOUR
T1 - Purification and characterisation of vanadium haloperoxidases from the brown alga Pelvetia canaliculata
AU - Almeida, M. G.
AU - Humanes, M.
AU - Melo, R.
AU - Silva, J. A.
AU - Fraústo Da Silva, J. J.R.
AU - Wever, R.
N1 - Funding Information:
JNICT/PRAXIS XXI/2/2.1/QUI/14/94 for financial support: Dr. J. Lampreia, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, for the stimulating interest, support and laboratory/equipment facilities.
PY - 2000/5/1
Y1 - 2000/5/1
N2 - Two enzymes characterised as iodoperoxidases (PcI and PcII), with vanadium-dependent activity, have been purified from the brown alga Pelvetia canaliculata (L.) Decne et Thur. (Fucaceae, Phaeophyceae), collected in the Northern Portuguese coast, at Viana do Castelo. The relative molecular masses were 166 kDa for PcI and 416 kDa for PcII, as determined by gel filtration. SDS-PAGE shows that PcI has just one band corresponding to a subunit of 66 kDa, while PcII shows four bands (66, 72, 157 and 280 kDa). The following kinetic parameters have been determined from a steady-state analysis of the oxidation of iodide by H2O2: PcI, pH(opt) = 6.0, K(M)(I-) = 2.1 mM, K(M)(H2O2) = 110 μM, K(i)(I-) = 127 mM; and PcII, pH(opt) = 6:5, K(M)(I- ) = 2.4 mM, K(M)(H2O2) = 20 μM and K(i)(I-) = 69 mM. These iodoperoxidases are thermostable, as also observed for vanadium bromo- and chloroperoxidases. (C) 2000 Elsevier Science Ltd.
AB - Two enzymes characterised as iodoperoxidases (PcI and PcII), with vanadium-dependent activity, have been purified from the brown alga Pelvetia canaliculata (L.) Decne et Thur. (Fucaceae, Phaeophyceae), collected in the Northern Portuguese coast, at Viana do Castelo. The relative molecular masses were 166 kDa for PcI and 416 kDa for PcII, as determined by gel filtration. SDS-PAGE shows that PcI has just one band corresponding to a subunit of 66 kDa, while PcII shows four bands (66, 72, 157 and 280 kDa). The following kinetic parameters have been determined from a steady-state analysis of the oxidation of iodide by H2O2: PcI, pH(opt) = 6.0, K(M)(I-) = 2.1 mM, K(M)(H2O2) = 110 μM, K(i)(I-) = 127 mM; and PcII, pH(opt) = 6:5, K(M)(I- ) = 2.4 mM, K(M)(H2O2) = 20 μM and K(i)(I-) = 69 mM. These iodoperoxidases are thermostable, as also observed for vanadium bromo- and chloroperoxidases. (C) 2000 Elsevier Science Ltd.
KW - Fucaceae
KW - Iodoperoxidases
KW - Pelvetia canaliculata
KW - Vanadium in biology
KW - Vanadium-dependent haloperoxidases
UR - http://www.scopus.com/inward/record.url?scp=0034113189&partnerID=8YFLogxK
U2 - 10.1016/S0031-9422(99)00602-0
DO - 10.1016/S0031-9422(99)00602-0
M3 - Article
C2 - 10846739
AN - SCOPUS:0034113189
SN - 0031-9422
VL - 54
SP - 5
EP - 11
JO - Phytochemistry
JF - Phytochemistry
IS - 1
ER -