Rubisco Evolution in C4 Eudicots: An Analysis of Amaranthaceae Sensu Lato

• DOI: 10.1371/journal.pone.0052974
• Publication Date: 2012-12-20T22:41:53Z
• Authors: Maxim V. Kapralov; J. Andrew C. Smith; Dmitry A. Filatov
• Keywords: Eudicots; Amaranthaceae; Ribulose; C4 Photosynthesis

Background Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) catalyses the key reaction in photosynthetic assimilation of CO2. In C4 plants CO2 is supplied to by an auxiliary CO2-concentrating pathway that helps maximize carboxylase activity enzyme while suppressing its oxygenase activity. As a consequence, exhibits higher maximum velocity but lower substrate specificity compared with C3 enzyme. Specific amino-acids are associated photosynthesis monocots, it not known whether selection has acted on similar way eudicots. Methodology/Principal Findings We investigated evolution Amaranthaceae sensu lato (including Chenopodiaceae), third-largest family plants, using phylogeny-based likelihood and Bayesian methods detect Darwinian chloroplast rbcL gene sample 179 species. Two residues, 281 309, were found be under positive multiple parallel replacements alanine serine at position methionine isoleucine 309. Remarkably, both have been detected other plant groups, such as illustrating striking parallelism molecular evolution. Conclusions/Significance Our findings illustrate how simple genetic changes can contribute strengthen hypothesis amino-acid adaptive Rubisco.