Journalartikel

Jahr der Veröffentlichung: 1998

Seiten: 857-863

Zeitschrift: Photochemistry and Photobiology

Bandnummer: 68

Heftnummer: 6

ISSN: 0031-8655

DOI Link: https://doi.org/10.1111/j.1751-1097.1998.tb05296.x

Verlag: Wiley

Abstract: 
The phytochrome-encoding gene Cerpu;PHY;2 (CP2) of the moss Ceratodon purpureus was heterologously expressed in Saccharomyces cerevisiae as a polyhistidine-tagged apoprotein and assembled with phytochromobilin (P Phi B) and phycocyanobilin (PCB), Nickel-affinity chromatography yielded a protein fraction containing approximately 80% phytochrome, The holoproteins showed photoreversibility with both chromophores, Difference spectra gave maxima at 644/716 nm (red-absorbing phytochrome [P-r]/far-red-absorbing phytochrome [P-fr]) for the PCB adduct, and 659/724 nm for the P Phi B-adduct, the latter in close agreement with values for phytochrome extracted from Ceratodon itself, implying that P Phi B is the native chromophore in this moss species, Immunoblots stained with the antiphytochrome antibody APC1 showed that the recombinant phytochrome had the same molecular size as phytochrome from Ceratodon extracts. Further, the mobility of recombinant CP2 holophytochrome on native size-exclusion chromatography was similar to that of native oat phytochrome, implying that CP2 forms a dimer, Kinetics of absorbance changes during the P-r --> P-fr photoconversion of the PCB adduct, monitored between 620 and 740 nm in the microsecond range, revealed the rapid formation of a red-shifted intermediate (I-700), decaying with a time constant of similar to 110 mu s. This is similar to the behavior of phytochromes from higher plants when assembled with the same chromophore, When following the formation of the P-fr state, two major processes were identified (with time constants of 3 and 18 ms) that are followed by slow reactions in the range of 166 ms and 8 s, respectively, albeit with very small amplitudes.

Harvard-Zitierstil: Zeidler, M., Lamparter, T., Hughes, J., Hartmann, E., Remberg, A., Braslavsky, S., et al. (1998) Recombinant phytochrome of the moss Ceratodan purpureus: Heterologous expression and kinetic analysis of P-r -> P-fr conversion, Photochemistry and Photobiology, 68(6), pp. 857-863. https://doi.org/10.1111/j.1751-1097.1998.tb05296.x

APA-Zitierstil: Zeidler, M., Lamparter, T., Hughes, J., Hartmann, E., Remberg, A., Braslavsky, S., Schaffner, K., & Gärtner, W. (1998). Recombinant phytochrome of the moss Ceratodan purpureus: Heterologous expression and kinetic analysis of P-r -> P-fr conversion. Photochemistry and Photobiology. 68(6), 857-863. https://doi.org/10.1111/j.1751-1097.1998.tb05296.x