Open AccessPurification and Characterization of Glucose Dehydrogenase from a Heterotrophically Grown Blue-Green Alga
Author(s) -
Warren M. Pulich,
Chase Van Baalen,
James W. Gibson,
F. Robert Tabita
Publication year - 1976
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.58.3.393
Subject(s) - nad+ kinase , dehydrogenase , biochemistry , flavin group , enzyme , polyacrylamide gel electrophoresis , biology , chemistry
NADP- and NAD-dependent glucose dehydrogenase was partially purified from a dark-grown blue-green alga (endophytic Nostoc strain MAC). Polyacrylamide gel electrophoresis established that a single protein possessed dual activity for either NADP or NAD. No other electron acceptor substituted for pyridine nucleotides and no evidence for a flavin prosthetic group was found. Although the Km for NADP was 8.8 mum and for NAD 328 mum, the enzyme was equally active with NAD or NADP at saturating levels of substrates. The enzyme was similar to previously described glucose dehydrogenase in that it had a high Km for glucose (18-20 mm at 35 C) and an alkaline pH optimum of 7.6 to 9.4.