Fig. 2

Identification of YqhD as the major glycolaldehyde reductase in E. coli. a Production of ethylene glycol by E. coli strains depending on the deletion of candidate glycolaldehyde reductases. Cells were cultivated on mineral (d)-xylose medium and exposed to 10 mM glycolaldehyde. Production of ethylene glycol was estimated after 10 h of incubation. b Log2 transformed expression levels of candidate glycolaldehyde reductases in wild-type cells (C1), strain Pen205 (ΔxylB expressing pEXT20-khk-C-aldoB) (C2), and wild-type cells exposed to 10 mM glycolaldehyde (C3). Genes were clustered according to the Euclidean distance between their expression levels using complete-linkage clustering [30]. Red and blue correspond to high and low expression levels, respectively, using arbitrary units.