Related Experiment Video
Updated: Jul 15, 2026

Protein-protein Interactions Visualized by Bimolecular Fluorescence Complementation in Tobacco Protoplasts and Leaves
Published on: March 9, 2014
Expression by Chlamydomonas reinhardtii of a chloroplast ATP synthase with polyhistidine-tagged beta subunits
Eric A Johnson1, Julian Rosenberg, Richard E McCarty
1Department of Biology, Johns Hopkins University, Baltimore, MD 21218-2685, USA. ejohn@jhu.edu
Abstract:
The green alga Chlamydomonas reinhardtii is a model organism for the study of photosynthesis. The chloroplast ATP synthase is responsible for the synthesis of ATP during photosynthesis. Using genetic engineering and biolistic transformation, a string of eight histidine residues has been inserted into the amino-terminal end of the beta subunit of this enzyme in C. reinhardtii. The incorporation of these amino acids did not impact the function of the ATP synthase either in vivo or in vitro and the resulting strain of C. reinhardtii showed normal growth. The addition of these amino acids can be seen through altered gel mobility of the beta subunit and the binding of a polyhistidine-specific dye to the subunit. The purified his-tagged CF1 has normal Mg(2+)-ATPase activity, which can be stimulated by alcohol and detergents and the enzyme remains active while bound to a nickel-coated surface. Potential uses for this tagged enzyme as a biochemical tool are discussed.
Related Concept Videos
Protein Transport to the Stroma
Protein complexes called the translocon of the outer chloroplast membrane or TOC complex, and the translocon of the inner chloroplast membrane or TIC complex mediate the...
ATP Synthase: Structure
ATP Synthase: Mechanism
Protein Transport to the Inner Chloroplast Membrane
Protein Transport to the Outer Chloroplast Membrane
Two models describe the mechanism of precursor recognition and entry across the outer membrane through the TOC complex. Model 1 suggests the newly synthesized precursor binds to the TOC receptor 159 and forms a complex.
Protein Transport to the Thylakoids

