Partial purification and initial characterization of phytochrome from the mossAtrichum undulatum P. Beauv. grown in the light

The extraction and partial purification of phytochrome from light-grownAtrichum undulatum P. Beauv., a chlorophyllous moss, is described. Polyethyleneimine and salt fractionation followed by hydroxyapatite and Affi-gel-blue chromatography were used to separate phytochrome from chlorophyll, and to purify the pigment. All steps were performed in the presence of Triton X-100 which improved the yield by a factor of about three. The protein has a molecular weight some-what larger than that ofAvena phytochrome (124 kDa), as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analysis. It cross-reacts with a monoclonal antibody against phytochrome from etiolated corn (Zea) and a polyclonal antibody against phytochrome from etiolated oat (Avena), and its photoreversibility is similar to that of phytochrome from greenAvena.Abbreviations EDTA ethylenediaminetetraacetic acid - FMN flavinmononucleotide - PMSF phenylmethylsulfonylfluoride - P_r(P_fr) red(far-red)-absorbing form of phytochrome - SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis