3-Hydroxypropionic acid (3-HP) is an important platform chemical for the biobased chemical industry. Lactobacillus reuteri produces 3-HP from glycerol via 3-hydroxypropionaldehyde (3-HPA) through a CoA-dependent propanediol utilization (Pdu) pathway. This study was performed to verify and evaluate the pathway comprising propionaldehyde dehydrogenase (PduP), phosphotransacylase (PduL), and propionate kinase (PduW) for formation of 3-HP from 3-HPA. The pathway was confirmed using recombinant Escherichia coli co-expressing PduP, PduL and PduW of L. reuteri DSM 20016 and mutants lacking expression of either enzyme. Growing and resting cells of the recombinant strain produced 3-HP with a yield of 0.3 mol/mol and 1 mol/mol, respectively, from 3-HPA. 3-HP was the sole product with resting cells, while growing cells produced 1,3-propanediol as co-product. 3-HP production from glycerol was achieved with a yield of 0.68 mol/mol by feeding recombinant E. coli with 3-HPA produced by L. reuteri and recovered using bisulfite-functionalized resin. (C) 2015 Elsevier Ltd. All rights reserved.