title: Biosynthesis of structurally novel carotenoids in Escherichia coli.
abstract: Previously, we utilized in vitro evolution to alter the catalytic functions of several carotenoid enzymes and produce the novel carotenoids tetradehydrolycopene and torulene in Escherichia coli. Here we report on the successful extension of these pathways and the C(30) carotenoid diaponeurosporene pathway with additional carotenoid genes. Extension of the known acyclic C(30) pathway with C(40) carotenoid enzymes-spheroidene monooxygenase and lycopene cyclase-yielded new oxygenated acylic products and the unnatural cyclic C(30) diapotorulene, respectively. Extension of acyclic C(40) pathways with spheroidene monooxygenase generated novel oxygenated carotenoids including the violet phillipsiaxanthin. Extension of the torulene biosynthetic pathway with carotene hydroxylase, desaturase, glucosylase, and ketolase yielded new torulene derivatives. These results demonstrate the utility of extending an in vitro evolved central metabolic pathway with catalytically promiscuous downstream enzymes in order to generate structurally novel compounds.
authors.affiliation: Department of Biochemistry, Molecular Biology, and Biophysics, 1479 Gortner Avenue, University of Minnesota, Saint Paul, MN 55108, USA.
authors.forename: Pyung Cheon
authors.initials: PC
authors.lastname: Lee
authors.forename: Abu Zafar Ruhul
authors.initials: AZ
authors.lastname: Momen
authors.forename: Benjamin N
authors.initials: BN
authors.lastname: Mijts
authors.forename: Claudia
authors.initials: C
authors.lastname: Schmidt-Dannert
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D002338:Carotenoids / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D013186:Farnesyl-Diphosphate Farnesyltransferase / Q000378:metabolism; D005798:Genes, Bacterial; D066298:In Vitro Techniques; D019753:Intramolecular Lyases / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000378:metabolism; D008956:Models, Chemical; D010957:Plasmids
chemical_list: D001426:Bacterial Proteins; D002338:Carotenoids; D006899:Mixed Function Oxygenases; C091056:CrtM protein, Staphylococcus aureus; D013186:Farnesyl-Diphosphate Farnesyltransferase; D019753:Intramolecular Lyases; C070925:lycopene cyclase-isomerase