Light and singlet oxygen in plant defense against pathogens: phototoxic phenalenone phytoalexins.
Plants defend themselves from pathogen infections or mechanical injury by a number of mechanisms, including the induced biosynthesis of antimicrobial secondary metabolites. These compounds, termed phytoalexins, represent a very economical way to counteract hazard, because the carbon and energy resources are diverted to phytoalexin synthesis only at the early period of attack and only at its site. The occurrence of phenalenone chromophores in phytoalexins of plants originally nonphototoxic suggests that these plants respond to pathogen attacks by biosynthesizing singlet oxygen photosensitizers able to use solar energy for defense. This concept may have implications for the development of novel crop protection strategies.
Flors
Cristina
C
Grup d'Enginyeria Molecular, Institut Químic de Sarrià, Universitat Ramon Llull, Via Augusta 390, 08017 Barcelona, Spain.
Nonell
Santi
S
D008027:Light; D043803:Phenalenes / Q000378:metabolism*; D010777:Photochemistry; D010935:Plant Diseases / Q000209:etiology / Q000382:microbiology*; D018521:Plant Physiological Phenomena; D012717:Sesquiterpenes; D026082:Singlet Oxygen; D013729:Terpenes / Q000378:metabolism*; D000094162:Phytoalexins
D043803:Phenalenes; D012717:Sesquiterpenes; D013729:Terpenes; D026082:Singlet Oxygen; C038036:phenalen-1-one; D000094162:Phytoalexins