Figure 5.
Analysis of S-oxygenation activity of FMOGS-OX1 to FMOGS-OX5 for methythioalkyl GSL. The activity of each recombinant FMOGS-OX was detected in assays using desulfo GSL extracts from Arabidopsis seed with a final concentration of 2 mm total desulfo GSL as substrate. Spheroplasts of E. coli expressing empty vector were used as negative control. A, Negative control; B, assay of FMOGS-OX1; C, assay of FMOGS-OX2; D, assay of FMOGS-OX3; E, assay of FMOGS-OX4; F, assay of FMOGS-OX5. Ratio of 4-MTB:(4-MTB + 4-MSB) was calculated to represent the S-oxygenating activity for short-chain GSL. The significance of the difference between the ratio 4-MTB:(4-MTB + 4-MSB) of the respective FMOGS-OX and the negative control was determined by ANOVA. For FMOGS-OX1 to FMOGS-OX4, P < 0.001; for FMOGS-OX5, P = 0.304. Ratio of 8-MTO:(8-MTO + 8-MSO) was calculated to represent the S-oxygenating activity for long-chain GSL. The significance of the difference between the ratio 8-MTO:(8-MTO + 8-MSO) of the respective FMOGS-OX and the negative control was determined by ANOVA. For FMOGS-OX1 to FMOGS-OX5, P < 0.001.