title: Isolation, sequence, and characterization of the Cercospora nicotianae phytoene dehydrogenase gene.
abstract: We have cloned and sequenced the Cercospora nicotianae gene for the carotenoid biosynthetic enzyme phytoene dehydrogenase. Analysis of the derived amino acid sequence revealed it has greater than 50% identity with its counterpart in Neurospora crassa and approximately 30% identity with prokaryotic phytoene dehydrogenases and is related, but more distantly, to phytoene dehydrogenases from plants and cyanobacteria. Our analysis confirms that phytoene dehydrogenase proteins fall into two groups: those from plants and cyanobacteria and those from eukaryotic and noncyanobacter prokaryotic microbes. Southern analysis indicated that the C. nicotianae phytoene dehydrogenase gene is present in a single copy. Extraction of beta-carotene, the sole carotenoid accumulated by C. nicotianae, showed that both light- and dark-grown cultures synthesize carotenoids, but higher levels accumulate in the light. Northern (RNA) analysis of poly(A)+ RNA, however, showed no differential accumulation of phytoene dehydrogenase mRNA between light- and dark-grown fungal cultures.
authors.affiliation: Department of Plant Pathology, North Carolina State University, Raleigh 27695.
authors.forename: M
authors.initials: M
authors.lastname: Ehrenshaft
authors.forename: M E
authors.initials: ME
authors.lastname: Daub
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002338:Carotenoids / Q000096:biosynthesis; D003001:Cloning, Molecular; D017124:Conserved Sequence; D005656:Fungal Proteins / Q000235:genetics; D005800:Genes, Fungal / Q000235:genetics*; D003904:Mitosporic Fungi / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000235:genetics*; D012331:RNA, Fungal / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D005656:Fungal Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D002338:Carotenoids; D010088:Oxidoreductases; C022398:phytoene dehydrogenase