TABLE 2.
Oxygenation products of A. nidulans PpoA Products of C16 and C18 fatty acids were identified as Me3Si ether methyl ester derivatives by GC/MS analysis after separation by RP-HPLC.
HPHME, hydroperoxyhexadecenoic acid; HPOME, hydroperoxyoctadecenoic acid; HPOTrE, hydroperoxyoctadecatrienoic acid; HPEME, hydroperoxyeicosenoic acid; HPEDE, hydroperoxyeicosadienoic acid; HPETrE, hydroperoxyeicosatrienoic acid; DiHHME, dihydroxyhexadenoic acid; DiHOME, dihydroxyoctadecenoic acid; DiHOTrE, dihydroxyoctadecatrienoic acid; DiHEME, dihydroxyeicosenoic acid; DiHEDE, dihydroxyeicosadienoic acid; DiHETrE, dihydroxyeicosatrienoic acid.
| Substrate | Product 1 | Product 2 |
|---|---|---|
| 16:1Δ9Z | 8-HPHME | 5,8-DiHHME |
| 18:1Δ9Z | 8-HPOME | 5,8-DiHOME |
| 18:2Δ9Z,12Z | 8-HPODE | 5,8-DiHODE |
| 18:3Δ9Z,12Z,15Z | 8-HPOTrE | 5,8-DiHOTrE |
| 20:1Δ11Z | 10-HPEMEa | 7,10-DiHEMEb |
| 20:2Δ11Z,14Z | 10-HPEDEa | 7,10-DiHEDEb |
| 20:3Δ11Z,14Z,17Z | 10-HPETrEa | 7,10-DiHETrEb |
Hydroperoxide fatty acids were unequivocally identified; the position of hydroperoxide was deduced from the corresponding dihydroxides.
Dihydroxy products of C20 fatty acids were identified by HPLC/tandem MS analysis and by detection of characteristic fragments: cleavage between C-7 and C-8 with formation of a characteristic signal at m/z 143 (HOOC-(CH2)5COH-) and cleavage between C-10 and C-11 with a characteristic signal at m/z 201 (HOOC-(CH2)5-COH-(CH2)2-COH-).