A peptide adhesive molded by magnesium glues Rubisco's subunits together

Abstract

Rubisco enzymes play central roles in carbon fixation, with potential importance in biotechnology, but have eluded a full description of their multistep assembly and function. A new article describes the fascinating discovery that some archaeal Rubiscos contain a built-in assembly domain inserted into an otherwise canonical Rubisco fold, providing a tremendous expansion of our understanding of the diversity of naturally occurring Rubiscos.

Figure 1.

Cartoon of the M. burtonii Rubisco assembly mechanism. Dimeric units of the Rubisco LSU are colored in shades of blue. RADs are colored red, and magnesium ions are colored yellow. In the L2 form (left), the structure of the RAD domain is unknown and may be partially unstructured. In the fully assembled L10 form (right), the RAD domain adopts a distinct tertiary fold and links the dimeric units to their neighbors via interfacial magnesium ion coordination. The occluded active sites (dashed lines) are now occupied by RuBP.