INVESTIGADORES
RUIZ Oscar Adolfo
artículos
Título:
The putrescine analogue 1-aminooxy-3-aminorpopane perturbs polyamine metabolism in the phytopathogenic fungus Sclerotinia sclerotiorum.
Autor/es:
GÁRRIZ A., DALMASSO M.C., PIECKENSTAIN F.L & O. A. RUIZ.
Revista:
ARCHIVES OF MICROBIOLOGY
Referencias:
Año: 2003 vol. 180 p. 169 - 175
ISSN:
0302-8933
Resumen:
We carried out the first evaluation of the effects of the putrescine analogue 1-aminooxy-3-aminopropane on fungal polyamine metabolism, by using Sclerotinia sclerotiorum as an experimental model. This compound inhibited ornithine decarboxylase, spermidine synthase, and S-adenosyl-methionine decarboxylase in mycelial extracts. Addition of 1-aminooxy-3-aminopropane at 1 mM to the culture medium did not reduce mycelial growth and caused a 29 % decrease in free spermidine and a 1 fold increase in free spermine. When added 4.5 h before the determination of ornithine decarboxylase, 1-aminooxy-3-aminopropane reduced in vivo activity of this enzyme by 40 to 50 %. On the other hand, when added 48 h before the determination, 1-aminooxy-3-aminopropane at 0.01 and 0.1 mM caused a slight increase of in vivo ornithine decarboxylase activity, while it had no effect at 1 mM. Comparison of the action of 1-aminooxy-3-aminopropane with that of other inhibitors of polyamine biosynthesis suggested that its effects on in vivo ornithine decarboxylase activity resulted from a balance between direct inhibition of enzyme activity and an indirect stimulation of enzyme synthesis and/or activity mediated by the decrease in spermidine levels, which in turn was due to the inhibition of spermidine synthase and S-adenosyl-methionine decarboxylase. The potential of 1-aminooxy-3-aminopropane as a tool for studies on fungal polyamine metabolism is discussed and for the control of plant diseases of fungal origin is discussed.