Chlorophyll a Synthesis in Rhodobacter sphaeroides by Chlorophyll Synthase of Nicotiana tabacum .

The production of phytylated chlorophyll (Chl ) in , which uses phytylated bacteriochlorophyll (BChl ), is the first step in expanding the light absorption spectra. Unlike the chlorophyll synthase (ChlG) of the sp. PCC6803, ChlGs of angiosperms, including , , , and , showed bacteriochlorophyll synthase activity and resistance to inhibition by bacteriochlorophyllide (BChlide ), geranylgeranylated BChl (BChl ), and BChl , collectively called bacteriochlorins. Among the angiosperm ChlGs, ChlG had the highest bacteriochlorophyll synthase activity and resistance to inhibition by bacteriochlorins. Expression of in resulted in the formation of free Chl in the presence of BChl during photoheterotrophic growth, even though reactive oxygen species were generated.