Method for the preparation of an evolved microorganism for the creation or the modification of metabolic pathways
AssigneeMetabolic Explorer
InventorsMichel Chateau, Benjamin Gonzalez, Isabelle Meynial-Salles, Philippe Noel Paul Soucaille, Olivier Zink
Life of this patent
Estimating the term…
Abstract
The present invention is directed to a method for the preparation of evolved microorganisms permitting the creation or modification of metabolic pathways. Strains of evolved microorganisms and evolved genes obtained by the method are also provided. The invention is also directed to the use of evolved microorganisms, genes or proteins in a biotransformation process.
Claims19
A method for producing a microorganism wherein said microorganism is obtained by selection of a modified microorganism, having a modified methionine biosynthesis pathway for the biosynthesis of methionine by metabolism of a simple carbon source and methylmercaptan as a source of sulfur, comprising:
- a) generating a modified microorganism by inactivating, deleting, or inhibiting expression of metE gene in an initial microorganism, wherein ability of said modified microorganism to grow is impaired when grown on a minimal medium containing no methionine, S-adenosylmethionine, homocysteine or cystathionine;
- b) culturing said modified microorganism obtained in step (a) on said minimal medium, in the presence of methylmercaptan under selection pressure thereby allowing said modified microorganism to proliferate through a methionine biosynthesis pathway to compensate for impaired growth;
- and
- c) selecting said microorganism from step (b) able to grow on said minimal medium in presence of methylmercptan,
- wherein the methionine biosynthesis pathway modifies such that methionine is produced by the metabolism of a simple carbon source and methylmercaptan as a source of sulfur thereby allowing said microorganism to proliferate on said minimal medium containing no methionine, S-adenosylmethionine, homocysteine or cystathionine.
A method for preparation of modified strains of E. coil having a modified methionine biosynthesis pathway for the biosynthesis of methionine by metabolism of a simple carbon source and methylmercaptan as a source of sulfur, comprising:
- (a) generating a modified microorganism by inactivating, deleting, or inhibiting expression of metE gene in an initial E. coil strain, wherein ability of said modified microorganism to grow is impaired when grown on a minimal medium containing no methionine, S-adenosylmethionine, homocysteine or cystathionine,
- b) culturing said modified microorganism obtained in step (a) on said minimal medium in presence of methylmercaptan under selection pressure thereby allowing said modified microorganism to proliferate through the methionine biosynthesis pathway to compensate for the impaired growth;
- and
- c) selecting an-evolved said E. coil strain from step (b) able to grow on said minimal medium in the presence of methylmercptan, said microorganism comprising a mutated metB gene with methionine synthase activity and allowing the direct conversion of O-succinyl-L-homoserine into L-methionine with methylmercaptan as a sulfur source.
Dependencies are inferred from the claim text.