Table 3.
FA distribution in the propargylcholine-labeled PC pool
| Abundance Ranking | pmol in 70 Subspecies | % of Total | Found in x of 140 Positions | |
|---|---|---|---|---|
| FA 16:0 | 1 | 1,276.3 | 36.5 | 18 |
| FA 18:1 | 2 | 1,169.8 | 33.4 | 18 |
| FA 16:1 | 3 | 310 | 8.9 | 15 |
| FA 18:0 | 4 | 161.2 | 4.6 | 11 |
| FA 20:4 | 5 | 129.9 | 3.7 | 8 |
| FA 18:2 | 6 | 84.8 | 2.4 | 14 |
| FA 14:0 | 7 | 77.5 | 2.2 | 10 |
| FA 20:3 | 8 | 63 | 1.8 | 7 |
| FA 22:5 | 9 | 47.5 | 1.4 | 6 |
| FA 20:1 | 10 | 34.9 | 1.0 | 6 |
| FA 22:6 | 11 | 32.9 | 0.9 | 3 |
| FA 22:1 | 12 | 23 | 0.7 | 1 |
| FA 22:4 | 13 | 21.7 | 0.6 | 4 |
| FA 20:2 | 14 | 16.7 | 0.5 | 5 |
| FA 20:5 | 15 | 15.7 | 0.4 | 3 |
| FA 18:3 | 16 | 9 | 0.3 | 3 |
| FA 22:0 | 17 | 8 | 0.2 | 2 |
| FA 16:2 | 18 | 5.5 | 0.2 | 2 |
| FA 24:1 | 19 | 4.8 | 0.1 | 1 |
| FA 22:3 | 20 | 4 | 0.1 | 2 |
| FA 22:2 | 21 | 3.4 | 0.1 | 1 |
| SFA | 1,523 | 43.5 | 41 | |
| MUFA | 1,543 | 44.1 | 41 | |
| PUFA | 434 | 12.4 | 58 |
PC, phosphatidylcholine; SFA, saturated fatty acid.
Total lipids isolated from bEND3 cells labeled with 20 μM lyso-propargyl-PC 16:0 for 24 h were analyzed using the azidopalmitate reporter method. Each lipid species was identified using the NL335.26 peak and the side chains by the respective FA fragment peaks. The two FAs were quantified as half of their sum, and the FA fragment peaks generated from pPC 31:1 served as internal standard. A total of 70 pPC subspecies carrying FA side chains at 140 possible positions were analyzed. FA amounts are shown as pmol per 45,000 cells and represent means; N = 7. The data correspond to the subspecies columns in Table 2.