My principal research interests lie in the field of microbial plankton (mostly phytoplankton) ecology, physiology and its biogeochemical role from the individual to community level in marine systems. I've worked on the relationship of phytoplankton metabolism and its relation to cell size. I measured metabolic rates such as respiration, exudation and carbon fixation of different marine phytoplankton species during different growth phases. This work allowed me to investigate to which extent the size-scaling of phytoplankton metabolism is dependent on the physiological state of the populations, as well as to identify differences between taxonomic groups in the growth phase-dependent dynamics of metabolic rates. Recently my work has been focused on the effect of oxidative stress (due to N-limited cells or UVB light) over the production of DMS(P) and also over the percentage of extracellular release of organic carbon in phytoplankton cultures and natural communities. The objective of my ongoing research in KAUST is to measure situ metabolic rates in the Red Sea plankton communities, characterize its variability and explore the effect of different stressors (e.g., UVB, nutrient limitation, virus infection) over photosynthetic rates (carbon fixation and exudation).