Production of 1,3-propanediol from glycerol using the newly isolated Klebsiella pneumoniae J2B

•The new isolate could efficiently produce PDO without forming pathogenic LPS.•Deletion of ldhA abolished lactate formation but with enhanced production of BDO.•Maximum PDO production was 58.0g/L with the productivity of 1.3g/L/h.•Product inhibition was considered major bottleneck for improving PDO production. Recently, novel Klebsiella pneumoniae J2B, which grows rapidly on glycerol as the carbon source without forming pathogenic and sticky lipopolysaccharides, was isolated. Current study examined the ability of K. pneumoniae J2B to produce 1,3-propanediol (PDO) from glycerol. To this end, a deletion mutant for lactate formation was constructed. The ldhA mutant strain produced negligible lactate but more 2,3-butanediol (BDO). When K. pneumoniae ΔldhA was cultivated in glycerol fed-batch mode, the PDO titer of 58.0g/L with a yield of 0.35g/g and an overall volumetric productivity of 1.3g/L/h were obtained. BDO was the main byproduct (26.6g/L). Less than 10g/L of the other metabolites was produced. As PDO and other metabolites accumulated, the rate of PDO production decreased significantly due mainly to the toxic effects of these metabolites. This study highlights the potential of newly isolated K. pneumoniae J2B for the production of PDO from glycerol.