Novel bacterial clade reveals origin of form I Rubisco

Douglas M. Banda, Jose H. Pereira, Albert K. Liu, Douglas J. Orr, Michal Hammel, Christine He, Martin A.J. Parry, Elizabete Carmo-Silva, Paul D. Adams, Jillian F. Banfield, Patrick M. Shih

Research output: Contribution to journalArticleResearchpeer-review

43 Citations (Scopus)

Abstract

Rubisco sustains the biosphere through the fixation of CO2 into biomass. In plants and cyanobacteria, form I Rubisco is structurally comprised of large and small subunits, whereas all other Rubisco forms lack small subunits. The rise of the form I complex through the innovation of small subunits represents a key, yet poorly understood, transition in Rubisco’s evolution. Through metagenomic analyses, we discovered a previously uncharacterized clade sister to form I Rubisco that evolved without small subunits. This clade diverged before the evolution of cyanobacteria and the origin of the small subunit; thus, it provides a unique reference point to advance our understanding of form I Rubisco evolution. Structural and kinetic data presented here reveal how a proto-form I Rubisco assembled and functioned without the structural stability imparted from small subunits. Our findings provide insight into a key evolutionary transition of the most abundant enzyme on Earth and the predominant entry point for nearly all global organic carbon.

Original languageEnglish
Pages (from-to)1158-1166+
Number of pages21
JournalNature Plants
Volume6
Issue number9
DOIs
Publication statusPublished - Sept 2020
Externally publishedYes

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