title: The problems of Prochloron.
abstract: Prokaryotic green algae (prochlorophytes), which contain chlorophylls a and b but no bilin pigments, may be phylogenetically related to ancestral chloroplasts if symbiogenesis occurred. They may be otherwise related to eukaryotic chlorophytes. They could have evolved from cyanophytes by loss of phycobilin and gain of chlorophyll b synthesis. These possibilities are briefly discussed. Relevant evidence from biochemical studies in many collaborative laboratories is now becoming available for the resolution of such questions.
mesh_terms: D005075:Biological Evolution; D002734:Chlorophyll / Q000096:biosynthesis; D000077194:Chlorophyll A; D000460:Chlorophyta / Q000145:classification / Q000502:physiology*; D002736:Chloroplasts; D010802:Phylogeny; D013559:Symbiosis
chemical_list: D002734:Chlorophyll; D000077194:Chlorophyll A