Date Published: January 01, 2018
Publisher: International Union of Crystallography
Author(s): Karin Valegård, Dirk Hasse, Inger Andersson, Laura H. Gunn.
The first crystal structure of Rubisco from A. thaliana is described and is compared with all other form I Rubisco crystal structures. This new structure is used to discuss the catalytic differences that could be conferred by alternative Rubisco small-subunit isoforms, and the potential benefit of differential expression of such isoforms on photosynthetic carbon assimilation in land plants.
Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyses the addition of carbon dioxide to ribulose 1,5-bisphosphate (RuBP) in the first step of the photosynthetic Calvin–Benson–Bassham cycle. However, molecular oxygen competes with carbon dioxide for addition to RuBP, which results in photorespiration: the production of a toxic compound, the recycling of which consumes energy and releases fixed CO2. Poor specificity (Sc/o) for substrate carbon dioxide, along with a slow catalytic turnover rate, means that Rubisco often limits the growth rate of higher plants (Long et al., 2006 ▸; Andersson, 2008 ▸).
The following references are cited in the Supporting Information for this article: Felsenstein (1985 ▸), Nei & Kumar (2000 ▸), Rzhetsky & Nei (1992 ▸), Saitou & Nei (1987 ▸) and Tamura et al. (2013 ▸).