Ecology and EvolutionEnvironmentResearch Scientist

Jacob J Valenzuela

Research Scientist

401 Terry Ave N
206-732-2102

Ocean Acidification and Diatoms: As atmospheric concentrations of the greenhouse gas, carbon dioxide (CO2) continues to meet climate change model predictions; the world’s oceans act as a carbon sink for CO2, which in turn decreases its pH, termed ocean acidification. Each year diatoms account for up to 40% of the total marine primary productivity. It is imperative we understand how the unicellular microalgae will respond to ocean acidification in order to more accurately model the consequences of climate change. We employ the model diatom, Thalassiosira pseudonana as a “canary’ during laboratory stress tests. In our version of a stress test, we put the diatom through a series of increasingly strenuous conditions (i.e. heat, UV, high light, etc.) and measure how well they can re-establish their correct physiology. The stress test reveals how resilient the system is to perturbations. Results have shown different population trajectories and phenotypic plasticity in response to high carbon environments. Diatoms at low pH are more resilient in their recovery from stress and their ability to re-establish the proper physiological state. 

Green Algae Biofuels: Chlamydomonas reinhardtii is a model green microalgae that produces lipid during nutrient stress. The bio-oil produced can be utilized for transportation fuel and energy production. Using systems biology we aim to uncover the regulatory and signaling networks of C. reinhardtii during state transitions from growth (biomass accumulation) to lipid accumulation. Such insights will be crucial for the rewiring networks for the produce a robust, high yield, biofuel production strain alga.  New molecular tools like CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) Cas9 gene editing can be deployed to rationally manipulate the genome to generate a more efficient biofuel strain of algae.

Publications

Valenzuela, Jacob J., Adrián López García de Lomana, Allison Lee, E. V. Armbrust, Mónica V. Orellana, and Nitin S. Baliga. “Ocean Acidification Conditions Increase Resilience of Marine Diatoms.” Nature Communications 9, no. 1 (June 13, 2018): 2328. https://doi.org/10.1038/s41467-018-04742-3. Cite
Imam, Saheed, Sascha Schauble, Jacob Valenzuela, Adrian Lopez Garcia de Lomana, Warren Carter, Nathan D. Price, and Nitin S. Baliga. “A Refined Genome-Scale Reconstruction of Chlamydomonas Metabolism Provides a Platform for Systems-Level Analyses.” The Plant Journal : For Cell and Molecular Biology 84, no. 6 (December 2015): 1239–56. https://doi.org/10.1111/tpj.13059. Cite
Lopez Garcia de Lomana, Adrian, Sascha Schauble, Jacob Valenzuela, Saheed Imam, Warren Carter, Damla D. Bilgin, Christopher B. Yohn, et al. “Transcriptional Program for Nitrogen Starvation-Induced Lipid Accumulation in Chlamydomonas Reinhardtii.” Biotechnology for Biofuels 8 (2015): 207. https://doi.org/10.1186/s13068-015-0391-z. Cite