Provided is a method for producing 1,3-propanediol by means of fermentation of a recombinant microorganism. First, a recombinant microorganism is provided; the recombinant microorganism can overexpress acetyl-CoA carboxylase genes: accBC and accDA, a malonyl-CoA synthetase gene: mcr, a 3-hydroxypropionyl-CoA synthetase gene: pcs, a 3-hydroxypropionyl-CoA reductase gene: pduP, and a 1,3-propanediol reductase gene: yqhD. The recombinant microorganism is subjected to fermentation culture in a flask or fermentor using glucose ad as raw material to obtain the 1,3-propanediol. The recombinant microorganism can utilize low-cost glucose, sucrose, molasses, xylose and the like as raw material in the fermentation process, without additional expensive vitamin B12. Thus, cost of the production is significantly reduced, and there is a promising prospect in market.

The present invention relates to recombinant Corynebacterium having 1,3-PDO productivity and reduced 3-HP productivity, and a method for producing 1,3-PDO by using same. When a Corynebacterium glutamicum variant according to the present invention is used, the productivity of 3-HP, which is a by-product, is inhibited by using low-cost glycerol as a carbon source, and thus 1,3-PDO can be produced with high efficiency.

The present invention discloses a bacterium and an obtaining method and application thereof. The bacterium has a property of coproducing 1,3-propanediol and D-lactic acid. Further, the bacterium is Klebsiella oxytoca, including Klebsiella oxytoca PDL-5 CCTCC M 2016185. The obtaining method of the bacterium may be to obtain the bacterium by directly screening wild bacteria that satisfy conditions from the environment or performing gene engineering modification to wild bacteria. The present invention has the advantages that the bacteria can coproduce 1,3-propanediol and D-lactic acid through fermentation, the molar conversion rate and the concentration of the two products are very high, the types of byproducts are few, the concentration is low, the product extraction process is simplified, the high-efficiency biological production of 1,3-propanediol and D-lactic acid can be realized, and the industrial application prospect is very great.

The present disclosure concerns recombinant yeast host cells having a first genetic modification for downregulating a first metabolic pathway that converts NADP.sup.+ to NADPH, as well as a second genetic modification for upregulating a second metabolic pathway that converts NADP.sup.+ to NADPH. The second genetic modification allows the expression of a glyceraldehyde-3-phosphate dehydrogenase lacking phosphorylating activity, which can, in some embodiments, be from enzyme commission 1.2.1.9 or 1.2.1.90. The second pathway is distinct from the first metabolic pathway. The present disclosure also concerns a process for making and improving the yield of a fermented product, such as ethanol, using the recombinant yeast host cell.

The present invention discloses a bacterium and an obtaining method and application thereof. The bacterium has a property of coproducing 1,3-propanediol and D-lactic acid. Further, the bacterium is Klebsiella oxytoca, including Klebsiella oxytoca PDL-5 CCTCC M 2016185. The obtaining method of the bacterium may be to obtain the bacterium by directly screening wild bacteria that satisfy conditions from the environment or performing gene engineering modification to wild bacteria. The present invention has the advantages that the bacteria can coproduce 1,3-propanediol and D-lactic acid through fermentation, the molar conversion rate and the concentration of the two products are very high, the types of byproducts are few, the concentration is low, the product extraction process is simplified, the high-efficiency biological production of 1,3-propanediol and D-lactic acid can be realized, and the industrial application prospect is very great.

A method for manufacturing 1,3-propanediol includes culturing, in the presence of a saccharide and formaldehyde to produce 1,3-propanediol, a microorganism having the following genes: (a) a first gene encoding an enzyme that catalyzes an aldol reaction between pyruvic acid and aldehydes; (b) a second gene encoding an enzyme that catalyzes a decarboxylation reaction of α-keto acids; and (c) a third gene encoding an enzyme that catalyzes a reduction reaction of aldehydes, is provided.

A method for manufacturing 1,3-propanediol includes culturing, in the presence of a saccharide and formaldehyde to produce 1,3-propanediol, a microorganism having the following genes: (a) a first gene encoding an enzyme that catalyzes an aldol reaction between pyruvic acid and aldehydes; (b) a second gene encoding an enzyme that catalyzes a decarboxylation reaction of α-keto acids; and (c) a third gene encoding an enzyme that catalyzes a reduction reaction of aldehydes, is provided.

Provided is a method for producing 1,3-propanediol by means of fermentation of a recombinant microorganism. First, a recombinant microorganism is provided; the recombinant microorganism can overexpress acetyl-CoA carboxylase genes: accBC and accDA, a malonyl-CoA synthetase gene, mcr, a 3-hydroxypropionyl-CoA synthetase gene: pcs, a 3-hydroxypropionyl-CoA reductase gene: pduP, and a 1,3-propanediol reductase gene: yqhD. The recombinant microorganism is subjected to fermentation culture in a flask or ferment or using glucose ad as raw material to obtain the 1,3-propanediol. The recombinant microorganism can utilize low-cost glucose, sucrose, malasses, xylose and the like as raw material in the fermentation process, without additional expensive vitamin B12. Thus, cost of the production is significantly reduced, and there is a promising prospect in market.

The present disclosure relates to a mutant microorganism in which a glycerol catabolic pathway and a 1,3-PDO biosynthetic pathway are introduced into a microorganism incapable of using glycerol as a carbon source, and a method of producing 1,3-PDO using the same. According to the present disclosure, it is possible to produce 1,3-PDO while growing a mutant microorganism having 1,3-PDO production ability by using the inexpensive raw material glycerol as a single carbon source. Thus, the present disclosure is useful for the economical production of 1,3-PDO.

The present invention relates to recombinant Corynebacterium having 1,3-PDO productivity and reduced 3-HP productivity, and a method for producing 1,3-PDO by using same. When a Corynebacterium glutamicum variant according to the present invention is used, the productivity of 3-HP, which is a by-product, is inhibited by using low-cost glycerol as a carbon source, and thus 1,3-PDO can be produced with high efficiency.