Affiliations: Department of Medicinal Chemistry and Molecular
Pharmacology, Purdue University, West Lafayette, IN 47907, USA | Department of Foods and Nutrition, Purdue University,
West Lafayette, IN 47907, USA
Note: [] Address for correspondence: Department of Medicinal Chemistry
and Molecular Pharmacology, 201 S. University Street, West Lafayette, IN
47907-2064, USA. Fax.: +1 765 494 4007; E-mail: [email protected]
Abstract: Human amyloid beta peptides Aβ1-40 and Aβ1-42 exhibit NADH
oxidase activity with regular oscillations at intervals of ca 6 min. In the
presence of copper, the oscillations in Aβ1-40 and Aβ1-42 become more
pronounced and now assume a period length of 24 min. In the presence of copper,
the oscillations are similar to those observed with NADH oxidase activities of
cell surface ECTO-NOX proteins in general including a period length of 24 min.
Solutions of copper sulphate in the presence of all the reagents except for the
peptides did not exhibit the oscillatory behavior. NOX proteins have been
reported previously to have properties of prions and to form amyloid rods of
indeterminant length similar to those formed by the 39–43 residue amyloid
beta proteins (Aβ). In this report, we demonstrate a second similarity
between ECTO-NOX proteins and amyloid beta, that of an oscillating NADH oxidase
activity with a period length of 24~min when assayed in the presence of
copper.
Keywords: amyloid beta, NADH (hydroquinone) oxidase, copper, neurodegeneration, time keeping
Journal: BioFactors, vol. 20, no. 4, pp. 221-235, 2004
