摘要:
The present invention concerns a new method combining evolution and rational design for the preparation of a strain of micro-organism for the production of 1,2-propanediol from a carbon source. The said method comprises growing an initial strain under selection pressure in an appropriate growth medium, said initial bacterial strain comprising an attenuation of the expression of the tpiA gene and an attenuation the expression of at least one gene involved in the conversion of methylglyoxal to lactate, in order to promote evolution in said initial strain; then selecting and isolating the evolved strain having an increased 1,2 propanediol production rate; then reconstructing a functional tpiA gene in the evolved strain. The present invention also concerns the evolved strain such as obtained, that may be furthermore genetically modified in order to optimize the conversion of a carbon source into 1,2-propanediol without bv-products and with the best possible yield.
摘要:
The present invention is related to a new method for replacing or deleting DNA sequences in Clostridia, with high efficiency, easy to perform and applicable at an industrial level. This method is useful to modify several genetic loci in Clostridia in a routine manner. This method is based on a replicative vector carrying at least two marker genes.
摘要:
The present invention concerns a modified microorganism with an increased methylglyoxal reductase activity, and its use for the preparation of 1,2-propanediol and/or acetol. In particular this increased methylglyoxal reductase activity is obtained by increasing the expression of specific genes from microorganisms.This invention is also related to a method for producing 1,2-propanediol and/or acetol by fermentation of a microorganism having an increased methylglyoxal reductase activity.
摘要:
The present invention concerns a new method combining evolution and rational design for the preparation of a strain of micro-organism for the production of 1,2-propanediol from a carbon source.The said method comprises: growing an initial strain under selection pressure in an appropriate growth medium, said initial bacterial strain comprising an attenuation of the expression of the tpiA gene and an attenuation the expression of at least one gene involved in the conversion of methylglyoxal to lactate, in order to promote evolution in said initial strain, then selecting and isolating the evolved strain having an increased 1,2 propanediol production rate, then reconstructing a functional tpiA gene in the evolved strain; The present invention also concerns the evolved strain such as obtained, that may be furthermore genetically modified in order to optimize the conversion of a carbon source into 1,2-propanediol without by-products and with the best possible yield.
摘要:
Microorganism useful for the production of 1,2-propanediol from a carbon source, wherein said microorganism is characterized by: an improved activity of the biosynthesis pathway from dihydroxyacetone phosphate to 1,2-propanediol, and an attenuated activity of the glyceraldehyde 3-phosphate dehydrogenase The invention is also related to a method for producing 1,2-propanediol by fermentation with a microorganism according to the invention.
摘要:
The present invention is related to a new method for replacing or deleting DNA sequences in Clostridia, with high efficiency, easy to perform and applicable at an industrial level. This method is useful to modify several genetic loci in Clostridia in a routine manner. This method is based on a replicative vector carrying at least two marker genes.
摘要:
The present invention is related to a recombinant microorganism optimized for the fermentative production of methionine, wherein the activity of the cobalamin-independent methionine synthase MetE is attenuated in said microorganism. The invention is also related to a method for producing methionine by fermentation.
摘要:
The invention relates to the use of polypropylene glycol as a shrinkage-reducing additive in dispersion powder compositions for construction materials containinga) a base polymer from the group consisting of vinyl ester polymers, (meth)acrylate and/or styrene (co)polymers and vinyl chloride polymers, andb) eitherb1) 2 to 20% by weight, based on the base polymer, of polyvinyl alcohol having a degree of hydrolysis of 85 to 94 mol % and a Hoppler viscosity of 2 to 40 mPa.s orb2) 2 to 20% by weight, based on the base polymer, of alkali metal salts or alkaline earth metal salts of phenolsulfonic acid-formaldehyde condensation products, andc) 3 to 30% by weight, based on the total weight of polymeric components, of fine antiblocking agents, whereind) the content of polypropylene glycol is 1 to 20% by weight, based on the base polymer.
摘要:
The present invention relates to a process for improving the production of methionine by culturing a microorganism modified for enhancing the expression of genes involved in succinate dehydrogenase synthesis. The microorganisms were modified in a way that the methionine/carbon source yield is increased. The isolation of methionine from the fermentation medium is also claimed.
摘要:
The present invention is related to a population of Clostridium acetobutylicum useful for the production of 1,3-propanediol (PDO), wherein said population comprises at least one strain of a Clostridium acetobutylicum sp. comprising mutations selected among the mutations identified in table 1, wherein relative percentages of said mutations are selected among specific genes.