Polyamine Metabolism during sclerotia development of Sclerotinia sclerotiorum.

GÁRRIZ A, GONZÁLEZ E, CAMPOS M, MENÉNDEZ A, RUIZ-HERRERA J, PIECKENSTAIN FL Y RUIZ OA

Iguazú. Misiones. Argentina

Congreso; XL Annual Meeting of the Argentine Society for Biochemistry and Molecular Biology Research (SAIB); 2004

Saciedad Argentina de Investigaciones Bioquímicas (SAIB)

Polyamines (putrescine, spermidine and spermine) are polycationic compounds found in all living organisms. They have shown to be essential for growth and morphogenesis of several fungi. We have previously studied polyamine metabolism on different steps of the life-cycle of Sclerotinia sclerotiorum (1, 2). In this work we evaluated polyamines requirement for sclerotial development, and the effect of polyamine biosynthesis inhibitors on this process. Neither a-difluoro-methylornithine nor cyclohexylamine, inhibitors of putrescine and spermidine biosynthesis respectively, reduced the number of sclerotia produced in vitro. By the contrary, mycelial growth was impaired. Furthermore, the activity of key polyamine biosynthetic enzymes, as well as free spermidine and spermine levels, diminished during sclerotial maturation. These results suggest that even though vegetative growth requires suitable levels of polyamines, sclerotial development in turn seems to be less dependent on polyamine biosynthesis. Further considerations on polyamine metabolism concerning sclerotia maturation and the potential use of polyamine biosynthesis inhibitors to control sclerotial-forming fungal phytopathogens are discussed. 1-Gárriz et al. Archives of Microbiology 180: 169-175. 2-Gárriz et al., New Phytologist 161: 847-854.