A novel phycocyanin-Chla/c2-protein complex isolated from chloroplasts of Chroomonas placoidea

Nine pigment-protein complexes were separated and characterized from intact Chroomonas placoidea chloroplasts by IEF. The bands I-VI with their isoelectric points (pI) values from 4 to 6 were phycocyanin components; bands VIII and IX (pI = 2.8-3.6) were chlorophyll-protein complexes. According to absorption and fluorescence spectra, band VII was designated as a novel phycocyanin-Chla/c2-protein complex (pI ≈ 3.4-3.7). These results indicated that phycocyanin is structurally and functionally coupled with chlorophyll-protein complex in C. placoidea, and probably interacted with electrostatic force in combination.