Molecular cloning and functional expression in E. coli of a novel plant enzyme mediating zeta-carotene desaturation.
We have cloned a cDNA from the plant Capsicum annuum which encodes a novel enzyme mediating the dehydrogenation of zeta-carotene and neurosporene to lycopene when expressed in E. coli cells accumulating zeta-carotene or neurosporene. This enzyme is unable to dehydrogenate either phytoene or lycopene. The deduced amino acid sequence suggests that this cDNA encodes a polypeptide whose mature size is ca. 59 kDa and which is synthesized as a precursor with a NH2-terminal extension resembling transit peptides for plastid targeting. Sequence comparison reveals 33-35% similarity with previously cloned plant or cyanobacterial phytoene desaturases. In contrast, only limited sequence similarity is found with a zeta-carotene desaturase from the cyanobacterium Anabaena.
Albrecht
M
M
Biosynthesis Group, Fachbereich Biologie, J.W. Goethe Universität, Frankfurt, Germany.
Klein
A
A
Hugueney
P
P
Sandmann
G
G
Kuntz
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D002338:Carotenoids / Q000378:metabolism*; D003001:Cloning, Molecular; D004798:Enzymes / Q000235:genetics / Q000302:isolation & purification*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000302:isolation & purification*; D010944:Plants / Q000201:enzymology*; D016415:Sequence Alignment
D004798:Enzymes; D010940:Plant Proteins; D002338:Carotenoids