The invention pertains to the field production of natural products and, in particular, in the field of production of cornexistin and hydroxycornexistin. It provides polynucleotides
10 encoding polypeptides involved in the biosynthesis of cornexistin and hydroxycornexistin as well as vectors and recombinant microorganisms comprising such polynucleotides. Also provided are methods for the production of natural products, in particular methods for the production of cornexistin and hydroxycornexistin, using such polynucleotides and
polpeptides encoded therein, as well as vectors and recombinant microorganisms
15 comprising such polynucleotides and polypeptides.
BACKGROUND OF THE INVENTION
Cornexistin and hydroxycornexistin are natural products derived from the fungus
Paecilomyces divaricatusformerly known as Paecilomyces veriotii SANK21086. Both,
20 cornexistin and hydroxycornexistin, are highly potent herbicides that have the unique quality of being harmless to corn plants. Because of this quality, both molecules have attracted research interest. The Sankyo Corporation discovered cornexistin during the screening of biological extracts for herbicidal use (JP2256602). Cornexistin showed good activity as a herbicide as well as relative inactivity towards corn plants. Sankyo' s characterization
25 showed this fungal natural product to be a member of the nonadride family, a group of natural products known for their interesting structural characteristics including a central nine-membered ring, fused maleic anhydrides and pendant alkyl chains. Cornexistin and hydroxycornexistin has been synthesized by chemical synthesis only as diastereomeres (Org. Biomol. Chem., 2008, 6, 4012- 4025). Nine-membered carbocyclic structures in
30 general are rare in nature and their synthesis as well as the genes involved in the synthesis are still unknown and not described.
Isolation of cornexistin from the cultures of Paecilomyces species originally identified as Paecilomyces variotii SANK21086 was published as early as 1989 by the Sankyo research group JP2256602). Later work from the DOW Elanco group described identification of
35 hydroxycornexistin also produced in Paecilomyces variotiiSANK 21086 (US00542478).
However, the yield of the producing strain SANK 21086 under fermentation conditions is believed to be too low for commercial production purposes.
The technical problem underlying the present invention can be seen as the provision of
40 additional means and methods for the production of cornexistin or hydroxycornexistin, or for the production of cornexistin and hydroxycornexistin. The technical problem is solved by the embodiments characterized in the claims and herein below.
PF
2
SUMMARY THE INVENTION
The invention provides for recombinant polynucleotides comprising nucleic acid
being