Biodegradation of polycyclic aromatic hydrocarbons in the surface ocean

• Main Author: Martínez Varela, Alícia
• Other Authors: Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Vila Costa, Maria, Piña Capó, Benjamí
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Universitat Politècnica de Catalunya 2022
• Subjects: Àrees temàtiques de la UPC::Enginyeria civil i ambiental; Subarctic
• Online Access: http://hdl.handle.net/2117/367550; http://hdl.handle.net/10803/674247; https://doi.org/10.5821/dissertation-2117-367550

Tesi en modalitat de compendi de publicacions Apèndix "Women in Science: Scientific contributions of female scientists relevant to this thesis" p. 320-321 Increasing quantities of organic pollutants (OP) are being released to the environment, posing a threat to Earth’s life system. In the marine environment, OP pollution caused by oil spill accidents receives a lot of academic and societal attention. However, the magnitude of semi-volatiles OP introduced by atmospheric deposition and by maritime currents is orders of magnitude larger. Little is known, however, about the cycling of these background OP in the oceans and their effects to marine ecosystems. It is believed that an important sink of OP in the marine environment must be microbial biodegradation, since it is widely recognized their capacity to consume many OPs. However, neither the magnitude of biodegradation, the identity of the main degraders nor OP effects to microorganisms, is known. Polycyclic aromatic hydrocarbons (PAH) and other semi-volatile hydrocarbons are among the most abundant OP in the marine environment. Their wide spectrum of physicochemical properties make PAH family an ideal surrogate to study the biogeochemistry of OP in seawater. This thesis focuses on the biodegradation activities under background concentrations of PAH in the upper ocean, and the co-occurring microbial responses to this exposure. The goals of this work are: 1) to get insights into microbial PAH biodegradation under realistic conditions in different upper ocean environments by means of biogeochemical, molecular and genomic approaches, 2) identify the main players and describe the main metabolisms co-occurring along with biodegradation in the interaction between PAH and microorganisms by means of physiological measurements and metatranscriptomic approaches, and 3) localize marine hot spots of PAH biodegradation and describe some of the main physicochemical influencing factors of biodegradation. For these purposes we did short term incubations with background ...