In situ Conversion of Chlorophyll b Reconstituted into Photosynthetic Protein LH2

Chlorophyll (Chl) b was successfully reconstituted into the binding sites of B800 bacteriochlorophyll a in bacterial light-harvesting protein LH2. The 7-formyl group in Chl b bound to LH2 was converted in situ to a hydroxymethyl group by NaBH4 without protein degradation. Chlorophyll (Chl) b, which is one of the major pigments in plants and green algae, is successfully reconstituted into the binding sites of B800 bacteriochlorophyll a in light-harvesting protein LH2 of a purple photosynthetic bacterium. The 7-formyl group in Chl b bound to LH2 is converted in situ to a hydroxymethyl group without degradation of the protein structure.