Study
on the properties of amine oxidase, superoxide dismutase and peroxidase
enzymes
This
project actually involves the University of Cagliari, Mansoura and Malta.
The research prevalently aims at the study of the metabolism and the
reaction mechanism of amine oxidases from mammals and plants and in
vitro study on antioxidant enzyme.
The research group of the University of Cagliari prevalently carries
out researches on the metabolism and reaction mechanism of copper containing
amine oxidase, in particular from Lens, Pisum seedlings, Euphorbia characias
latex, and from Pig kidney.
This enzyme catalyzes the oxidation of primary amines, in mono-, di-
and polyamines to the corresponding aldehydes and in particular it is
involved in the catabolism of putrescine, spermine and spermidine, which
are important agents in various processes such as tissue differentiation,
cellular proliferation, growth of tumors and transformation of cultured
cells. Amine oxidases are soluble, dimeric enzymes containing two copper
atoms and two organic prosthetic groups identified as TOPA, the quinone
of 2,4,5-trihydroxyphenylalanine.
Together with the studies of substrate specificity and inhibitors, recently
the kinetics of reaction between Lens amine oxidase and various substrates,
and the study on the active site of Cu-amine oxidase and from Lens esclulenta
and from Euphorbia characias latex., have been described.
On Euphorbia enzyme are in
progress further studies on DNA molecule to define the nucleotide sequence
of the active site. In parallel to these studies, there is a great interest
about comparative studies on antioxidant enzymes such as peroxidases
and superoxide dismutases. Peroxidases have been found in most plant
cells and seem to be a normal component of such cells. The wide distribution
of the enzyme suggests that it could be of great biological importance.
The work groups performed the purification and characterization of different
peroxidases from Opuntia ficus indica fruits, from Oryza sativa and
Hordeun vulgare seedlings. Also a Cu-Zn-superoxide dismutase from Oryza
sativa seed has been purified.
Moreover, it has been studied the effect on the neurotoxin 6-hydroxydopamine
by superoxide dismutase, catalase, ceruloplasmin and peroxidase, and
some explanations of why these proteins may increase or reduce the rate
of autoxidation of 6-hydroxydopamine has been reported.
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University of Cagliari (Italy) - All right reserved
University
of Cagliari - Italy
University
of Msida - Malta
University
of Mansoura - Egypt