Reconstitution of the Peridinin–chlorophyll a Protein (PCP): Evidence for Functional Flexibility in Chlorophyll Binding

Autor: Roger G. Hiller, Julian Catmull, Frank P. Sharples, Robert Puskeiler, David J. Miller, Helen Tweedale
Rok vydání: 2005
Předmět:
Zdroj: Photosynthesis Research. 86:229-240
ISSN: 1573-5079
0166-8595
DOI: 10.1007/pl00022067
Popis: The coding regions for the N-domain, and full length peridinin-chlorophyll a apoprotein (full length PCP), were expressed in Escherichia coli. The apoproteins formed inclusion bodies from which the peptides could be released by hot buffer. Both the above constructs were reconstituted by addition of a total pigment extract from native PCP. After purification by ion exchange chromatography, the absorbance, fluorescence excitation and CD spectra resembled those of the native PCP. Energy transfer from peridinin to Chl a was restored and a specific fluorescence activity calculated which was approximately 86% of that of native PCP. Size exclusion analysis and CD spectra showed that the N-domain PCP dimerized on reconstitution. Chl a could be replaced by Chl b, 3-acetyl Chl a, Chl d and Bchl using the N-domain apo protein. The specific fluorescence activity was the same for constructs with Chl a, 3-acetyl Chl a, and Chl d but significantly reduced for those made with Chl b. Reconstitutions with mixtures of chlorophylls were also made with eg Chl b and Chl d and energy transfer from the higher energy Qy band to the lower was demonstrated.
Databáze: OpenAIRE