LAUSR

Scientists find a way to build the major plant enzyme RuBisCO in bacteria Among the thousands of different enzymes that have evolved in nature, ribulose-1,5-bisphosphate carboxylase-oxygenase (known as RuBisCO) holds a special place. It is the enzyme in plants, algae, and many photosynthetic bacteria that ultimately takes energy derived from the Sun and uses it to convert or “fix” atmospheric CO2 into organic forms of carbon that constitute the basis for life (1). Globally, RuBisCO fixes enormous quantities (gigatons) of carbon annually. To carry out such a massive chemical conversion requires a huge amount of the enzyme, especially because RuBisCO performs reactions quite slowly. Accordingly, RuBisCO is believed to be the most abundant enzyme on the planet (1, 2). RuBisCO is unusual in other ways as well. Each RuBisCO enzyme in the cell requires a tremendous amount of help, from chaperones, to fold into the correct three-dimensional shape required for its function. The large number of chaperones is important for two reasons. One is that there are numerous questions about the identities of these chaperones and how they operate on a structural level. Another is that it has been difficult to produce correctly folded RuBisCO in laboratory experiments, which has also limited the ability to engineer alternate forms of the enzyme. On page 1272 of this issue, Aigner et al. (3) fill in some of the most important remaining pieces of the RuBisCO folding and assembly puzzle.