IBIMOL   23987
INSTITUTO DE BIOQUIMICA Y MEDICINA MOLECULAR PROFESOR ALBERTO BOVERIS
Unidad Ejecutora - UE
artículos
Título:
Physiological responses and toxin production of Microcystis aeruginosa in short-term exposure to solar UV radiation
Autor/es:
MALANGA, GABRIELA; SEDAN, DANIELA; HERNANDO, MARCELO; HOUGHTON, CHRISTIAN; ROSSO, LORENA; MINAGLIA, MELINA CELESTE CRETTAZ; ANDRINOLO, DARÍO; GIANNUZZI, LEDA; MALANGA, GABRIELA; SEDAN, DANIELA; HERNANDO, MARCELO; HOUGHTON, CHRISTIAN; ROSSO, LORENA; MINAGLIA, MELINA CELESTE CRETTAZ; ANDRINOLO, DARÍO; GIANNUZZI, LEDA
Revista:
Photochemical and Photobiological Sciences
Editorial:
ROYAL SOC CHEMISTRY
Referencias:
Lugar: CAMBRIDGE; Año: 2017 vol. 17 p. 69 - 80
ISSN:
1474-905X
Resumen:
The aim of this study was to evaluate the effects of short- term (hours) exposure to solar UV radiation (UVR, 280-400nm) on the physiology of Microcystis aeruginosa. Three solar radiation treatments were implemented: (i) PAR (PAR, 400-700nm), (ii) TUVA (PAR+UVAR, 315-700nm) and (iii) TUVR (PAR+UVAR+UVBR, 280-700nm). Differential responses of antioxidant enzymes and reactive oxygen species (ROS) production to UVR were observed. Antioxidant enzymes were more active with high UVR doses. However, different responses were observed depending on the exposure to UVAR or UVBR and the dose level. No effects were observed on biomass, ROS production or increased activity of superoxide dismutase (SOD) and catalase (CAT) compared to control when UVR+PAR doses were lower than 9875 kJ m-2. For intermediate doses, UVR+PAR doses between 9875 and 10275 kJ m-2, oxidative stress increased while resistance was imparted through SOD and CAT in cells exposed to UVAR. Despite increased antioxidant activity, biomass decrease and photosynthesis inhibition were observed but no effects were observed with added exposure to UVBR. At the highest doses (UVR+PAR higher than 10275 kJ m-2), the solar UVR caused decreased photosynthesis and biomass with only activation of CAT by UVBR and SOD and CAT by UVAR. In addition, for such doses, significant decreases of microcystins (MCs, measured as MC-LR equivalents) were observed as consequence of UVAR. This study facilitates our understanding of the SOD and CAT protection according to UVAR and UVBR doses and cellular damage and reinforces the importance of UVR as an environmental stressor. In addition, our results support the hypothesized antioxidant function of MCs.