Aldo-keto reductase (AKR) that displays broad substrate specificity in vitro. Is able to reduce the standard AKR substrates DL-glyceraldehyde, D-erythrose, methylglyoxal, p-nitrobenzaldehyde, benzaldehyde and butyraldehyde, in the presence of NADPH. Cannot use NADH as a cosubstrate. Does not act on glucose, 2-pyridine carboxyaldehyde, fructose and xylose. The physiological function of this enzyme is not clear. May play a role in bacterial stress response and/or in detoxification of reactive aldehydes. kcat is 1.37 sec(-1) with DL-glyceraldehyde as substrate (PubMed:12554958). kcat is 1.09 sec(-1) with p-nitrobenzaldehyde as substrate (PubMed:12554958). kcat is 4.02 sec(-1) with D-erythrose as substrate (PubMed:15019785). kcat is 5.33 sec(-1) with methylglyoxal as substrate (PubMed:15019785). kcat is 2.59 sec(-1) with benzaldehyde as substrate (PubMed:15019785). kcat is 3.96 sec(-1) with butyraldehyde as substrate (PubMed:15019785). Monomer. Is under the control of the sigma-B transcription factor. Is induced by heat shock, salt stress, oxidative stress, glucose limitation and oxygen limitation. Belongs to the aldo/keto reductase family. Aldo/keto reductase 11 subfamily.