Title: UV-induced damage in bacterioneuston: mechanisms and ecological implications
Abstract:UVB (280-315 nm) levels at the surface of the Earth are expected to increase in upcoming years with important consequences for ecosystem function. Bacteria play a crucial role in the function of ecosystems, but are also particularly susceptible to the deleterious effects of UV radiation. This thesis investigated the mechanisms by which UV radiation affects bacteria.
The results obtained indicate that: (i) Bacterioneuston is more UVB resistant than bacterioplankton (Santos et al., 2012a); (ii) Damage to lipids and proteins may underlie the different UV sensitivity among bacteria (Santos et al., 2013a); (iii) Singlet oxygen is pivotal in UVB-induced inactivation (Santos et al., 2012b) and metal homeostasis is crucial to limit the detrimental effects of irradiation (Santos et al., 2013b); (iv) UV-induced damage depends on chemical water properties and on growth conditions preceding irradiation (Santos et al., 2013c).
Acknowledgments: FCT (SFRH/BD/40160/2007), CESAM and University of Aveiro.
Santos AL, Oliveira V, Baptista I, Henriques I, Gomes NCM, Almeida A, Correia A, Cunha A. (2012a), Effects of UV-B radiation on the structural and physiological diversity of bacterioneuston and bacterioplankton. Appl. Environ. Microbiol. 78, 2066-2069.
Santos AL, Moreirinha C, Lopes D, Esteves AC, Henriques I, Almeida A, Domingues MRM, Delgadillo I, Correia A, Cunha A. (2013a), Effects of UV Radiation on the Lipids and Proteins of Bacteria Studied by Mid-Infrared Spectroscopy.Environ. Sci. Technol. 47, 6306-6315.
Santos AL, Gomes NCM, Henriques I, Almeida A, Correia A, Cunha A.(2012b), Contribution of reactive oxygen species to UV-B-induced damage in bacteria. J. Photochem. Photobiol. B. 117, 40-46.
Santos AL, Gomes NCM, Henriques I, Almeida A, Correia A, Cunha A.(2013b), Role of Transition Metals in UV-B Induced Damage to Bacteria. Photochem. Photobiol. 89, 640-648.
Santos AL, Gomes NCM, Henriques I, Almeida A, Correia A, Cunha A.(2013c), Growth conditions influence UVB sensitivity and oxidative damage in an estuarine bacterial isolate. Photoch. Photobio. Sci. 12, 974-986.
PhD Degree: Biology, Specialty: Microbiology; Year of conclusion: 2013
Institution: University of Aveiro, Portugal
Supervision: Ângela Cunha and António Correia (CESAM, Univ. Aveiro)