Scientists at the University of California San Diego have discovered new plant enzymes that can allow them to save water while consuming more CO2 from the atmosphere. The enzyme causes the plants to react to CO2 and change how they use their pores and by modifying the enzyme, scientists believe that could be developed more CO2- and drought-tolerant crops.
Plants use tiny breathing pores that emit H2O and bring in CO2. Until now, researchers knew that the pores can tighten to save water when there is enough CO2 in the atmosphere, but they didn’t know how. These researchers have identified the pair of proteins that control a plant’s response to high CO2 and dry conditions.
“A lot of plants have a very weak response to CO2. So even though atmospheric CO2 is much higher than it was before the industrial age and is continuing to increase, there are plants that are not capitalizing on that. They’re not narrowing their pores, which would allow them to take in CO2, while losing less water,” he said. “It could be that with these enzymes, you can improve how efficiently plants use water, while taking in CO2 for photosynthesis. Our data in the lab suggest that the CO2 response can be cranked up.” said Julian Schroeder, professor of biology at the University of California, San Diego.
Carbonic anhydrases are the proteins, enzymes that split CO2 into protons and bicarbonate. Plants with disabled generates for the enzymes fail to respond to high CO2 concentrations in the air and don’t save water. By adding normal carbonic anhydrase genes the plants were able to restore the CO2-triggered pore-tightening response in mutant plants. However, according to the team the results are promising because foe each molecule of CO2 plants consumes they lose 44 percent less water.