Fig. 5

Phenylacetaldehyde analysis using PAAS heterologously expressed in Escherichia coli. A GC–MS results showing that Me1G_2960, Me2G_2381, Me3G_0317, Me3G_1222, Me3G_2284, Me4G_0535, and Me5G_1302 encode enzymes that are functional when expressed in Escherichia coli. Extract ion chromatogram shows products produced by strains expressing target genes or the empty vector control (CK). Peaks at retention time about 8 min represent phenylacetaldehyde. X-axis represents retention time; Y-axis represents relative abundance. B Mass spectrum of phenylacetaldehyde (molecular ion m/z 91). C Concentration of phenylacetaldehyde produced by products of 9 PAAS genes. Data (mean values ± SEs) were obtained from three replicate experiments (Student’s t-test, *P < 0.05, **P < 0.01)