Xanthophyll interconversion

Yamamoto HY, Nakayama TOM and Chichester CO (1962) Studies on the light and dark interconversion of leaf Xanthophylls. Arch Biochem Biophys 97 168-173 Zechmeister L (1934) Carotinoide, ein biochemischer Berichte uber pflanzliche und tierische Polyenfarbstoffe. Springer Verlag,Berlin... 

Violaxanthin and zeaxanthin undergoing interconversion in the xanthophyll cycle have been found to be present not only in a fraction of pigments mobile within the thylakoid membrane but also to remain in a dynamic equilibrium between the thylakoids, where the main xanthophyll cycle enzymes are localized, and the chloroplast envelope (Siefermaim-Harms et al., 1978)... 

Three carotenoids, violaxanthin (3), antheraxanthin (18), and zeaxanthin (15), undergo rapid, light-induced changes in concentration. These interconversions sometimes are called the xanthophyll cycle (Fig. 26.11) (Demmig-Adams and Adams, 1993). The content of violaxanthin in leaves can be reversibly altered in plants by exposure to light. In the presence of light, violaxanthin is deepoxidized to produce first antheraxanthin and then zeaxanthin. This... 

The possibility that epoxide carotenoids may function in oxygen evolution and transport has been suggested. In higher plants, three xanthophylls— violaxanthin, zeaxanthin, and antheraxanthin—undergo a series of photoin-duced interconversions (violaxanthin cycle) (Fig. 15), as reviewed by Hager (1975). Evidence as to the significance of this cycle is not conclusive, however. Two Russian workers, Sapozhnikov and Saakov, support the conclusion that the violaxanthin cycle is involved in oxygen transport (for review, see Sapozhnikov, 1973). However, other workers have concluded that ca-... 

---