alexa A novel homodimeric geranyl diphosphate synthase from the orchid Phalaenopsis bellina lacking a DD(X)2-4D motif.
Chemistry

Chemistry

Natural Products Chemistry & Research

Author(s): Hsiao YY, Jeng MF, Tsai WC, Chuang YC, Li CY,

Abstract Share this page

Abstract SUMMARY: Geranyl diphosphate (GDP) is the precursor of monoterpenes, which are the major floral scent compounds in Phalaenopsis bellina. The cDNA of P. bellina GDP synthase (PbGDPS) was cloned, and its sequence corresponds to the second Asp-rich motif (SARM), but not to any aspartate-rich (Asp-rich) motif. The recombinant PbGDPS enzyme exhibits dual prenyltransferase activity, producing both GDP and farnesyl diphosphate (FDP), and a yeast two-hybrid assay and gel filtration revealed that PbGDPS was able to form a homodimer. Spatial and temporal expression analyses showed that the expression of PbGDPS was flower specific, and that maximal PbGDPS expression was concomitant with maximal emission of monoterpenes on day 5 post-anthesis. Homology modelling of PbGDPS indicated that the Glu-rich motif might provide a binding site for Mg(2+) and catalyze the formation of prenyl products in a similar way to SARM. Replacement of the key Glu residues with alanine totally abolished enzyme activity, whereas their mutation to Asp resulted in a mutant with two-thirds of the activity of the wild-type protein. Phylogenetic analysis indicated that plant GDPS proteins formed four clades: members of both GDPS-a and GDPS-b clades contain Asp-rich motifs, and function as homodimers. In contrast, proteins in the GDPS-c and GDPS-d clades do not contain Asp-rich motifs, but although members of the GDPS-c clade function as heterodimers, PbGDPS, which is more closely related to the GDPS-c clade proteins than to GDPS-a and GDPS-b proteins, and is currently the sole member of the GDPS-d clade, functions as a homodimer. This article was published in Plant J and referenced in Natural Products Chemistry & Research

Relevant Expert PPTs

Relevant Speaker PPTs

  • Ines Bouaziz
    Water treatment containing organic compounds by coupling adsorption and electrochemical degradation at BDD anode: Sawdust adsorption performance for the treatment of dilute phenol solutions
    PPT Version | PDF Version
  • Lavanya Rayapu
    EVALUATION OF ANTI-DIABETIC PROPERTIES OF THE COMPOUNDS ISOLATED FROM MARINE MACROALGAE
    PPT Version | PDF Version
  • Heidi Schalchli
    Natural products of Anthracophyllum discolor: Ligninolytic enzymes and antifungal volatile compounds
    PPT Version | PDF Version
  • Soliman Khatib
    Analysis of volatile organic compounds in rats with dopaminergic lesion: possible application for early detection of Parkinson’s disease
    PPT Version | PDF Version
  • Adel Nefzi
    “Adel Nefzi-Torrey-Pines-Institute-for-Molecular-Studies-USA-Diversity-Oriented-Synthesis-of-low-Molecular-Weight-Acyclic-and-Heterocyclic-Compounds-from-Resin-bound-Polyamides-Application-for-Drug-Discovery”
    PPT Version | PDF Version
  • Pietro Tedesco
    Exploiting the cold environments: psychrophilic bacteria as a promising source of novel bioactive compounds
    PPT Version | PDF Version

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords