Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Phytochrome from green plants: assay, purification, and characterization

Technical Report ·
DOI:https://doi.org/10.2172/5687950· OSTI ID:5687950
Phytochrome from the chlorophyllous cells of light-grown higher plants and green algae has been isolated and characterized. We have developed a simple procedure that separates chlorophyll from phytochrome in crude extracts from green tissue thus permitting spectral measurement of the phytochrome in such extracts for the first time. Spectral and immunochemical analysis of phytochrome from green oat tissue indicates the presence of two distinct species of the molecule: a minority species (approx. 20%) that is recognized by antibodies directed against phytochrome from etiolated tissue and that has an apparent molecular mass of 124 kilodaltons (kD), the same as that of the native molecule from etiolated tissue; and a majority species (approx. 80%) that is not recognized by anti-etiolated tissue phytochrome Ig and has a Pr absorbance maximum some 14 nm shorter than its etiolated tissue counterpart. Mixing experiments have established that these different molecular species preexist in the green cell and are not the results of posthomogenization modifications. Attempts to purify the phytochrome from green tissue by immunoaffinity chromatography have been thwarted by the lack of immunological cross-reactivity referred to. We have begun to identify monoclonal antibodies specific for antigenic sites distributed throughout the length of the etiolated-tissue phytochrome polypeptide. Axenic cultures of the alga Mesotaenium have been established and preliminary spectral analysis of phytochrome isolated from these cells has been carried out.
Research Organization:
Wisconsin Univ., Madison (USA)
DOE Contract Number:
AC02-81ER10903
OSTI ID:
5687950
Report Number(s):
DOE/ER/10903-4; ON: DE83017447
Country of Publication:
United States
Language:
English