Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Tsegaye Arficho - BCCC
Co-Author(s): Binika Chunara and Amrita Madabushi, BCCC, MD Stephen Miller, UMBC, MD
Growing concerns over climate change are driving interest in development of renewable bioenergy to replace fossil fuels. Genetic manipulation of algae can make biofuel production more efficient. The photosynthetic green alga Chlamydomonas reinhardtii is a well-studied model organism that is easy to grow and manipulate at the molecular genetic level. This project focusses on a set of genes believed to be important for a carbon-concentrating mechanism (CCM) that acclimates algae to normal, CO2-limiting conditions. Carbonic anhydrases are components of the CCM that catalyze the interconversion of carbon dioxide and bicarbonate, and thereby make inorganic carbon more accessible to the cell. The purpose of this project is to increase the intracellular concentrations of CO2 in C. reinhardtii by overexpressing periplasmic and thylakoid membrane carbonic anhydrases, CAH1 and CAH3, respectively. C. reinhardtii CAH1 and CAH3 coding regions were synthesized with C. reinhardtii codon bias and epitope tags and the gene fragments were subcloned into expression vector pARG which contains the ARG7 gene required for arginine biosynthesis. We transformed the CAH1and CAH3 vectors into an arg7 mutant strain and selected several ARG survivors for western blot analysis to determine the expression of protein. We will select the best expressing lines for growth curve and dry weight analyses to determine whether the transformants overexpressing CAH1 or CAH3 are able to grow faster than the wild-type C. reinhardtii strain. In future both genes could be expressed together. The next step will be to manipulate these methods for microalgae that naturally produce higher lipid levels than C. reinhardtii, such as Chlorella vulgaris.
Funder Acknowledgement(s): These results were obtained as part of the Research Experience and Mentoring (REM) program in the Department of Biological Sciences at the University of Maryland Baltimore County. This program is funded by a grant (REM supplement to NSF-EFRI-1332344) from the National Foundation (NSF) Directorate for Engineering (ENG) Office of Emerging Frontiers in Research and Innovation (EFRI).
Faculty Advisor: Stephen Miller, email@example.com
Role: all the parts