Genetic manipulation of carotenoid biosynthesis: strategies, problems and achievements

Carotenoids. some of which are provitamin A, have a range of diverse biolog ical functions and actions, especially in relation to human health. For exa mple, carotenoids are known to be crucial for normal vision end have been a ssociated with reducing the risk of several degenerative diseases including cancer. The putative advantage of modifying and engineering the carotenoid biosynthetic pathways is obvious: to provide sources for the isolation of desired carotenoids or to generate food plants with increased carotenoid co ntent. This article reviews the studies of carotenoid production in heterol ogous microorganisms and the engineering of crop plants using manipulated c arotenoid biosynthesis.