Microorganism modified for the production of 1,3-propanediol

A modified microorganism for producing 1,3-propanediol (PDO) from a carbon substrate, the microorganism comprising:

• a pathway for synthesis of 2,4-dihydroxybutyrate (DHB);
• and
• a three-step metabolic pathway comprising:
• conversion of DHB to obtain 2-oxo-4-hydroxybutyrate (OHB) by an enzyme having DHB dehydrogenase activity,
• decarboxylation of the OHB to obtain 3-hydroxypropionaldehyde by an enzyme having 2-oxo-4-hydroxybutyrate decarboxylase activity, and
• reduction of the obtained 3-hydroxypropionaldehyde to obtain PDO with an enzyme having 3-hydroxypropionaldehyde reductase activity,
• wherein:
• the gene encoding the enzyme having DHB dehydrogenase activity is selected from the group consisting of IdhA from Lactococcus lactis, lldD from Escherichia coli, lldD from E. coli carrying a mutation at position Val108 (by reference to SEQ ID No. 122), mdh from E. coli, mdh from Bacillus subtilis, and mdh from E. coli carrying a mutation in at least one position selected from the group consisting of (by reference to SEQ ID No. 124):
• Ile12, Arg81, Lys82, Met85, Asp86, Val93, Ile117, Gly179, Thr211, and Met227 (by reference to SEQ ID No.126);
• the gene encoding the enzyme having 2-oxo-4-hydroxybutyrate decarboxylase activity is selected from the group consisting of PDC1, PDC5, PDC6, ARO10, and THIS genes from Saccharomyces cerevisiae;
• kivD and kdcA genes from Lactococcus lactis;
• pdc gene from Clostridium acetobutylicum;
• PDC2 and PDC3 genes from Arabidopsis thaliana;
• PDC1, PDC2, and ARO10 genes from Pichia stipitis;
• pdc gene from Zymomonas mobilis;
• sucA gene from Escherichia coli;
• dxs gene from Escherichia coli;
• pdc gene from Z. mobilis carrying a mutation in at least one position selected from the group consisting of:
• Tyr290, Trp392, Gly413, and Ile476 (by reference to SEQ ID No.128);
• and kdcA gene from L. lactis carrying a mutation in at least one position selected from the group consisting of:
• Gln377, Phe381, Phe382, Gly402 Val461, Ile465, and Phe542 (by reference to SEQ ID No.130);
• and
• the enzyme having 3-hydroxypropionaldehyde reductase activity is:
• a gene product encoded by a gene selected from the group consisting of yqhD, fucO, dkgA, and dkgB genes from Escherichia coli, dhaT gene from K. pneumoniae, and ADH1 and ADH2 genes from Saccharomyces cerevisiae, or
• an enzyme having 3-hydroxypropionaldehyde reductase activity obtained by at least one mutation of an enzyme, said mutation improving activity and/or substrate affinity of the enzyme for 3-hydroxypropionaldehyde.