title: The putrescine analogue 1-aminooxy-3-aminopropane perturbs polyamine metabolism in the phytopathogenic fungus Sclerotinia sclerotiorum.
abstract: The effects of the putrescine analogue 1-aminooxy-3-aminopropane on fungal polyamine metabolism were evaluated using Sclerotinia sclerotiorum as an experimental model. The 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 two-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 40-50%. 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 indirect stimulation of enzyme synthesis and/or activity mediated by the decrease in spermidine levels, which in turn was due to 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 and for the control of plant diseases of fungal origin is discussed.
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús, Universidad Nacional de General San Martín-Consejo Nacional de Investigaciones Científicas y Técnicas, Casilla de Correo 164, 7130, Chascomús, Buenos Aires, Argentina.
authors.forename: Andrés
authors.initials: A
authors.lastname: Gárriz
authors.forename: María C
authors.initials: MC
authors.lastname: Dalmasso
authors.forename: Fernando L
authors.initials: FL
authors.lastname: Pieckenstain
authors.forename: Oscar A
authors.initials: OA
authors.lastname: Ruiz
mesh_terms: D012437:Adenosylmethionine Decarboxylase / Q000187:drug effects / Q000378:metabolism; D001203:Ascomycota / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D015317:Biogenic Polyamines / Q000096:biosynthesis*; D009955:Ornithine Decarboxylase / Q000187:drug effects / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology*; D011437:Propylamines / Q000378:metabolism / Q000494:pharmacology*; D011700:Putrescine / Q000031:analogs & derivatives; D011436:Spermidine Synthase / Q000187:drug effects / Q000378:metabolism
chemical_list: D015317:Biogenic Polyamines; D011437:Propylamines; C046252:1-aminooxy-3-aminopropane; D011436:Spermidine Synthase; D009955:Ornithine Decarboxylase; D012437:Adenosylmethionine Decarboxylase; D011700:Putrescine