Abstract
cis-Prenyltransferase catalyzes the sequential condensation of isopentenyl diphosphate with allylic diphosphate to synthesize polyprenyl diphosphates that play vital roles in cellular activity. Despite potential significance of cis-prenyltransferase in plant growth and development, no gene of the enzyme has been cloned from higher plants. Using sequence information of the conserved region of cis-prenyltransferase cloned recently from Escherichia coli, Micrococcus luteus, and yeast, we have isolated and characterized the first plant cis-prenyltransferase from Arabidopsis thaliana. Sequence analysis revealed that the protein is highly homologous in several conserved regions to cis-prenyltransferases from M. luteus, E. coli, and yeast. In vitro analyses using the recombinant protein overexpressed in E. coli revealed that the enzyme catalyzed the formation of polyprenyl diphosphates ranging in carbon number from 100 to 130 with a predominance of C(120). The enzyme exhibited a higher affinity for farnesyl diphosphate than for geranylgeranyl diphosphate, with the K(m) values being 0.13 and 3.62 micrometer, respectively, but a lower affinity for isopentenyl diphosphate, with a K(m) value of 23 micrometer. In vitro rubber biosynthesis analysis indicated that the Arabidopsis cis-prenyltransferase itself could not catalyze the formation of higher molecular weight polyprenyl diphosphates similar to natural rubber. A reverse transcriptase-polymerase chain reaction analysis showed that the gene was expressed at low levels in Arabidopsis plant, in which expression of the cis-prenyltransferase in leaf and root was higher than that in stem, flower, and silique. These results indicate the tissue-specific expression of cis-prenyltransferase and suggest a potential role and significance of the enzyme in the polyisoprenoid biosynthesis in plants.
Highlights
Prenyltransferase is an enzyme that catalyzes the synthesis of linear prenyl diphosphates involved in the biosynthesis of various isoprenoid compounds, including sterols, carotenoids, The nucleotide sequence(s) reported in this paper has been submitted to the GenBankTM/EBI Data Bank with accession number(s) AF162441
In vitro rubber biosynthesis analysis indicated that the Arabidopsis cis-prenyltransferase itself could not catalyze the formation of higher molecular weight polyprenyl diphosphates similar to natural rubber
Two genes are the structural genes for undecaprenyl diphosphate synthase, which catalyzes the formation of undecaprenyl diphosphate (C55) that serves as a glycosyl carrier lipid during the biosynthesis of cell wall polysaccharide components in Escherichia coli and Micrococcus luteus (24 –26)
Summary
Prenyltransferase is an enzyme that catalyzes the synthesis of linear prenyl diphosphates involved in the biosynthesis of various isoprenoid compounds, including sterols, carotenoids, The nucleotide sequence(s) reported in this paper has been submitted to the GenBankTM/EBI Data Bank with accession number(s) AF162441. Based on the configuration of isoprene units in the final reaction products, prenyltansferases are classified into two classes: trans- and cis-prenyltransferase In both prokaryotes and eukaryotes, trans-prenyltransferases catalyze the formation of isoprenoid compounds, such as geranyl diphosphate (C10), farnesyl diphosphate (FPP1; C15), and geranylgeranyl diphosphate (GGPP; C20), which serve as initiating molecules to produce many other longer chain length isoprenoid compounds necessary for cellular growth and survival. This paper is available on line at http://www.jbc.org cis-Prenyltransferase from A. thaliana ferase and to verify the role of these conserved amino acid sequences for the catalytic activity of the enzyme, it is necessary to identify and clone more genes for cis-prenyltransferase from different organisms including animals and plants. It is of critical importance to test whether cis-prenyltransferase could catalyze the formation of higher molecular weight polymers similar to natural rubber (cis-1,4-polyisoprene), which is synthesized by the action of a rubber polymerase or rubber transferase that catalyzes the sequential condensation of IPP with allylic diphosphates similar to cis-prenyltransferase
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
