摘要:

The subcellular localization of the iridoids loganin and secologanin was studied in a secologanin accumulatingCatharanthus roseuscell culture. Vacuoles were isolated from protoplasts by an osmotic shock treatment, followed by flotation centrifugation. The iridoid contents of cells, protoplasts and vacuoles were analysed by HPLC. Secologanin was found to be stored exclusively in the vacuoles. In loganin fed cells, loganin accumulated in the vacuoles while vacuolar secologanin contents increased, indicating that the conversion of loganin to secologanin occurs in the vacuoles. However, feedings of loganin to isolated protoplasts and vacuoles did not result in increased secologanin levels.

ISSN:1253-8078    

DOI:10.1080/12538078.1999.10515806

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The slightly bitter taste ofChicorium intybusL. originates from sesquiterpene lactones with come through precursors formedviafanesyl diphosphate by a sesquiterpene cyclase. The first step of this biosynthesis is the (+)-germacrene A.

ISSN:1253-8078    

DOI:10.1080/12538078.1999.10515807

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The functional yeastERG19allele encoding mevalonate diphosphate decarboxylase (MVD) and the mutated recessive alleleerg19leading to a decrease of sterol production and a thermosensitive phenotype, were cloned and characterized. The mutatederg19allele bears a single amino acid leu79-to- pro substitution. This mutation doesn't affect the level of production of the mutated enzyme. Two—hybrid assays showed that the yeast MVD forms homodimers; the single point mutation was shown to impair the dimerization of the mutated enzyme, leading to a less active MVD.

ISSN:1253-8078    

DOI:10.1080/12538078.1999.10515808

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:1253-8078    

DOI:10.1080/12538078.1999.10515795

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor