LOX-induced lipid peroxidation mechanism responsible for the detrimental effect of marine diatoms on zooplankton grazers.
Some marine diatoms negatively affect the reproduction of dominant zooplankton grazers such as copepods, thus compromising the transfer of energy through the marine food chains. In this paper, the metabolic mechanism that leads to diatom-induced toxicity is investigated in three bloom-forming microalgae. We show that copepod dysfunctions can be induced by highly reactive oxygen species (hROS) and a blended mixture of diatom products, including fatty acid hydroperoxides (FAHs); these compounds display teratogenic and proapoptotic properties. The process is triggered by the early onset of lipoxygenase activities that elicit the synthesis of species-specific products, the basic structures of which were established (1-20); these compounds boost oxidative stress by massive lipid peroxidation. Our study might explain past laboratory and field results showing how diatoms damage zooplankton grazers even in the absence of polyunsaturated aldehydes, a class of molecules that has been formerly implicated in mediating the toxic activity of diatoms on copepods.
Fontana
Angelo
A
CNR, Istituto di Chimica Biomolecolare, Via Campi Flegrei 34, 80078, Pozzuoli, Napoli, Italy. afontana@icmib.na.cnr.it
d'Ippolito
Giuliana
G
Cutignano
Adele
A
Romano
Giovanna
G
Lamari
Nadia
N
Massa Gallucci
Alexia
A
Cimino
Guido
G
Miralto
Antonio
A
Ianora
Adrianna
A
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D033342:Copepoda / Q000187:drug effects* / Q000254:growth & development; D017377:Diatoms / Q000187:drug effects* / Q000254:growth & development; D015227:Lipid Peroxidation / Q000187:drug effects* / Q000502:physiology; D008054:Lipid Peroxides / Q000378:metabolism; D008084:Lipoxygenase / Q000633:toxicity*; D009682:Magnetic Resonance Spectroscopy; D008386:Marine Biology; D013058:Mass Spectrometry; D018384:Oxidative Stress / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D015048:Zooplankton / Q000187:drug effects* / Q000254:growth & development
D008054:Lipid Peroxides; D017382:Reactive Oxygen Species; D008084:Lipoxygenase