Peridinin Peridinin Peridinin is a light-harvesting apocarotenoid, a pigment associated with chlorophyll and found in the peridinin-chlorophyll-protein (PCP) light-harvesting complex in dinoflagellates, best studied in "Amphidinium carterae". Peridinin is an apocarotenoid pigment that some organisms use in photosynthesis. Many photosynthetic dinoflagellates use peridinin, which absorbs blue-green light in the 470-550nm range, outside the range accessible to chlorophyll molecules. The peridinin-chlorophyll-protein complex is a specialized molecular complex consisting of a boat-shaped protein molecule with a large central cavity that contains peridinin, chlorophyll, and lipid molecules, usually in a 4:1 ratio of peridinin to chlorophyll. Peridinin chlorophyll (PerCP) is commonly used in immunoassays
Photosynthetic pigment other groups of bacteria use the bacteriochlorophyll pigments (similar to the chlorophylls) for photosynthesis. Unlike the cyanobacteria, these bacteria do not produce oxygen; they typically use hydrogen sulfide rather than water as the electron donor. Recently, a very different pigment has been found in some marine γ-proteobacteria: proteorhodopsin. It is similar to and probably originated from bacteriorhodopsin (see below: under Archaea). Bacterial chlorophyll b has been isolated from Rhodopseudomonas spp. but its structure is not yet known to us. Halobacteria use the pigment bacteriorhodopsin which acts directly as a proton pump when exposed to light. Photosynthetic pigment A photosynthetic pigment