Abstract
The recombinant 65-kDa polypeptide of phyA oat phytochrome was expressed by yeast Pichia pastoris and assembled into two chromopeptides with the chromophores phytochromobilin (PΦB) and phycocyanobilin (PCB), respectively. The P r and P fr states of the two protein variants were characterized by resonance Raman (RR) spectroscopy and compared with native phyA oat phytochrome demonstrating that the deletion of the C-terminal half of phyA does not alter the structure of the chromophore site within the N-terminal half. Most of the RR spectral changes observed upon replacing PΦB by PCB can be attributed exclusively to altered vibrational mode compositions due to the different ring D substitutions (vinyl vs. ethyl), implying that the chromophore structures are largely the same for PΦB- and PCB-assembled phytochromes. Only in the P r state may the RR spectral changes also reflect subtle differences of the PΦB and PCB conformations in the 65-kDa phyA, presumably brought about by the specific steric requirements of the vinyl and ethyl groups.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
