Towards engineering carboxysomes into C3 plants

Plant J. 2016 Jul;87(1):38-50. doi: 10.1111/tpj.13139. Epub 2016 Jun 20.

Abstract

Photosynthesis in C3 plants is limited by features of the carbon-fixing enzyme Rubisco, which exhibits a low turnover rate and can react with O2 instead of CO2 , leading to photorespiration. In cyanobacteria, bacterial microcompartments, known as carboxysomes, improve the efficiency of photosynthesis by concentrating CO2 near the enzyme Rubisco. Cyanobacterial Rubisco enzymes are faster than those of C3 plants, though they have lower specificity toward CO2 than the land plant enzyme. Replacement of land plant Rubisco by faster bacterial variants with lower CO2 specificity will improve photosynthesis only if a microcompartment capable of concentrating CO2 can also be installed into the chloroplast. We review current information about cyanobacterial microcompartments and carbon-concentrating mechanisms, plant transformation strategies, replacement of Rubisco in a model C3 plant with cyanobacterial Rubisco and progress toward synthesizing a carboxysome in chloroplasts.

Keywords: Nicotiana; Rubisco; Synechococcus elongatus; carbon-concentrating mechanism; carboxysome; chloroplast; chloroplast transformation; photosynthesis; transgenic; transplastomic.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Carbon / metabolism*
  • Carbon Dioxide / metabolism
  • Chloroplasts / metabolism
  • Photosynthesis / genetics
  • Photosynthesis / physiology
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism*
  • Ribulose-Bisphosphate Carboxylase / genetics
  • Ribulose-Bisphosphate Carboxylase / metabolism
  • Synechococcus / genetics
  • Synechococcus / metabolism
  • Tobacco / genetics
  • Tobacco / metabolism

Substances

  • Bacterial Proteins
  • Carbon Dioxide
  • Carbon
  • Ribulose-Bisphosphate Carboxylase