Chloroplast Biogenesis 34: SPECTROFLUOROMETRIC CHARACTERIZATION IN SITU OF THE PROTOCHLOROPHYLL SPECIES IN ETIOLATED TISSUES OF HIGHER PLANTS.

The fluorescence emission and excitation properties of protochlorophyll in etiolated cucumber (Cucumis sativus L.) cotyledons and primary bean (var. Red Kidney) leaves were characterized at 77 K. Contrary to previous studies, it appears that the short-wavelength protochlorophyll emission band consists of four fluorescent components, instead of only one nonphototransformable protochlorophyll. It was demonstrated that etiolated cucumber cotyledons synthesize and accumulate nontransformable protochlorophyll (E(440), F(630)) as well as short-wavelength phototransformable protochlorophyll (E(433), F(633)), (E(444), F(636)), and (E(445), F(640)). Long-wavelength phototransformable protochlorophyll (E(450), F(657)) is also formed. In this context, E refers to the Soret excitation maxima and F refers to the red emission maxima of the protochlorophylls.IN ETIOLATED BEAN LEAVES, THE CORRESPONDING SPECIES WERE: nontransformable protochlorophyll (E(440), F(630)), short-wavelength phototransformable protochlorophylls (E(441), F(633)), (E(442), F(636)), and (E(443), F(640)), and long-wavelength phototransformable protochlorophyll (E(447), F(657)).