Fig 1. Lipidomics of T. gondii tachyzoites identifies a novel parasite lipid, PtdThr.

(A) Elution profile showing the retention times and relative abundance of lipids isolated from extracellular tachyzoites (10⁷). X1 represents a previously unknown lipid. (B) MS analysis of X1 fraction revealing PtdThr, PtdSer, and PEtn-Cer species. Individual lipids were identified by their fragmentation patterns and m/z ratios in the negative ionization mode. (C) MS/MS spectrum of X1-derived major peak (m/z 850.5) from panel B. Note the neutral loss of 101 Da (transition from 850.5 to 749.6). Acyl chains (sn-1, 20:1; sn-2, 20:4) were identified by their masses.