You are here because of a single, all-important enzyme. But don’t look inward to find ribulose-1,5-bisphosphate carboxylase/oxygenase, known more mercifully among scientists as rubisco. Instead, look to the food you eat and the trees that manufacture oxygen, as this is the protein that makes photosynthesis possible. Without it, life on Earth as we know it would not exist.
For all that heavy lifting, rubisco is remarkably inefficient. The enzyme converts carbon dioxide into sugars that sustain plants. But it is easily confused, and will react with oxygen in a process that creates a toxic byproduct, wastes energy, and limits how quickly plants can grow. (Which is not to fault rubisco: This is a very difficult reaction to pull off, and just look at how many plants have been getting it right for hundreds of millions of years.) That includes the essential crops that feed humanity — grains, vegetables, fruits — that could theoretically grow better if their rubisco worked more efficiently. This problem becomes more urgent as global temperatures rise, because this essential protein gets even less efficient in t... Read more
