摘要:
In accordance with the present invention, a novel aromatic prenyltransferase, Orf2 from Streptomyces sp. strain CL190, involved in naphterpin biosynthesis has been identified and the structure thereof elucidated. This prenyltransferase catalyzes the formation of a C-C bond between a prenyl group and a compound containing an aromatic nucleus, and also displays C-O bond formation activity. Numerous crystallographic structures of the prenyltransferase have been solved and refined, e.g., (1) prenyltransferase complexed with a buffer molecule (TAPS), (2) prenyltransferase as a binary complex with geranyl diphosphate (GPP) and Mg2+, and prenyltransferase as ternary complexes with a non-hydrolyzable substrate analogue, geranyl S-thiolodiphosphate (GSPP) and either (3) 1,6-dihydroxynaphthalene (1,6-DHN), or (4) flaviolin (i.e., 2,5,7-trihydroxy-1,4-naphthoquinone, which is the oxidized product of 1,3,6,8-tetrahydroxynaphthalene (THN)). These structures have been solved and refined to 1.5 Å, 2.25 Å, 1.95 Å and 2.02 Å, respectively. This first structure of an aromatic prenyltransferase displays an unexpected and non-canonical (beta/alpha)-barrel architecture. The complexes with both aromatic substrates and prenyl containing substrates and analogs delineate the active site and are consistent with a proposed electrophilic mechanism of prenyl group transfer. These structures also provide a mechanistic basis for understanding prenyl chain length determination and aromatic co-substrate recognition in this structurally unique family of aromatic prenyltransferases. This structural information is useful for predicting the aromatic prenyltransferase activity of proteins.
摘要:
PROBLEM TO BE SOLVED: To obtain a gene cluster involved in the non-mevalonate pathway of Hevea brasiliensis and determine the base sequences of these genes. SOLUTION: The gene cluster involved in the non-mevalonate pathway of Hevea brasiliensis was obtained and the base sequences of these genes were determined. The gene cluster involved in the IPP(isopentenyl diphosphate) biosynthesis in the non-mevalonate pathway is involved in the biosynthesis of vitamin E and carotenoids. Therefore, the Hevea brasiliensis obtained by introducing the gene cluster can be expected to produce high-quality rubber with improved permanence. COPYRIGHT: (C)2007,JPO&INPIT
摘要:
The present invention provides nucleotide and peptide sequences of an isolated cDNA coding for sunflower farnesyl pyrophosphate synthase, a key enzyme for the structurally diverse class of isoprenoid biosynthetic metabolites. The present invention also provides the recombinant plant expression vector comprising said nucleotide sequences and for the host cell into which said DNA sequence in the recombinant plant expression vector has been introduced to produce transgenic tobacco plants. Transgenic plants expressing heterologous farnesyl pyrophosphate synthase show 2-fold increase in seed production, higher chlorophyll contents in leaves and stronger drought-stress tolerance, as compared to non-transgenic or control vector-transformed tobacco plants.