Peridinin-chlorophyll-protein complex by the CATH database, which systematically classifies protein structures, as an "alpha solenoid" fold; however, elsewhere in the literature the term alpha solenoid is used for open and less compact helical protein structures. Photosynthetic dinoflagellates contain membrane-bound light-harvesting complexes similar to those found in green plants. They additionally contain water-soluble protein-pigment complexes that exploit carotenoids such as peridinin to extend their photosynthetic capacity. Peridinin absorbs light in the blue-green wavelengths (470 to 550 nm) which are inaccessible to chlorophyll by itself; instead the PCP complex uses the geometry of the relative pigment orientations to effect extremely high-efficiency energy transfer from
Chlorophyll c Chlorophyll c Chlorophyll "c" is a form of chlorophyll found in certain marine algae, including the photosynthetic Chromista (e.g. diatoms, brown algae) and dinoflagellates. It has a blue-greenish color and is an accessory pigment, particularly significant in its absorption of light in the 447-452 nm wavelength region, Like chlorophyll a and chlorophyll b, it helps the organism gather light and passes a quanta of excitation energy through the light harvesting antennae to the photosynthetic reaction centre. Chlorophyll "c" is unusual because it has a porphyrin ring structure and does not have an isoprenoid tail or a reduced ring D, features