Mapping of a carotenogenic gene cluster fromErwinia herbicolaand functional identification of six genes

Six genes have been mapped and identified by hybridization or by carotenoid analysis of deletion mutants on a 9 kb chromosomal fragment originating from Erwinia herbicola Eho 10. These genes include crtB, E and I which have been formerly described for Rhodobacter, and three new ones: crtZ encoding lycopene cyclase, crtH for beta-carotene hydroxylase, and crtG for zeaxanthin glycosilase. Their arrangement on the plasmid has been elucidated.