Allophycocyanin

Part of speech: noun

Definitions

1. A blue light-harvesting protein pigment found in cyanobacteria and red algae that helps capture light energy for photosynthesis
2. A bluish accessory pigment complex in photosynthetic cyanobacteria and certain algae, used to absorb light and pass its energy along
3. The blue phycobiliprotein found in the photosynthetic apparatus of cyanobacteria and red algae, which gathers light for energy conversion

Etymology: Allophycocyanin is a compound built from two parts: "allo-", from the Ancient Greek "ắllos" meaning "other" or "different", and "phycocyanin", the blue pigment of algae. The prefix signals a close relative of that pigment, one with a slightly different molecular makeup. Phycocyanin itself gets its name from "phyco-", from the Greek "phykos" meaning "seaweed" or "alga", combined with "cyanin", from the Greek "kyanos" meaning "dark blue". Allophycocyanin therefore literally means something like "the other seaweed-blue", a name that points to its place in the family of algal light-harvesting proteins. Chemists coined the term in modern scientific research, not in classical antiquity, and the word is used mainly in biochemistry and photosynthesis studies to describe the pigment's role in capturing light.