Table I.
Fatty acid composition of the R. leguminosarum biovar viciae 5523 and the mutant 5808 lipid A preparations
| FAME-TMS | Distribution of fatty acids in lipid A (%) |
|
|---|---|---|
| 5523 | 5808 | |
| C16:0 | 1.1 | 1.9 |
| C18:0 | 1.7 | 0.3 |
| β-ΟHC14:0 | 42 | 37 |
| β-ΟHC15:0 | 4.6 | 3.5 |
| β-ΟHC16:0 | 18 | 21 |
| β-ΟHC18:0 | 32 | 36 |
| 27-OHC28:0 (VLCFA) | ++ | ++ |
β-ΟHC14:0, β-hydroxymyristic acid; β-ΟHC16:0, β-hydroxypalmitic acid; β-ΟHC18:0, β-hydroxystearic acid; β-ΟHC15:0, β-hydroxypentadecanoic acid. VLCFA 27-OHC28:0 (27-hydroxyoctacosanoic acid) was present in substantial amounts (i.e., the GC peak area of its fatty acid methyl ester was as large as that of β-OHC14:0) but not quantified. However, MALDI-TOF-MS analysis (see Figures 6 and 7 and Table II) showed that all lipid A structures present contain one 27-OHC28:0 moiety. Trace amounts of C16:0 and C18:0 were also detected, possibly due to slight contamination by phospholipids.