Figure 4.

Identification and tentative structural assignment of novel AR IPLs produced by T. kodakarensis. Fragmentations, retention times, and parent ion masses of AR IPLs were identified after ion trap-MS and Q-TOF-MS. MS/MS spectra (left column) revealed major ions that corresponded to fragmentation of headgroup moieties as denoted in the dark grey box; Inos = inositol. Tentative molecular structures are provided in the right column, where R = archaeol. (A) IPL-5; the MS/MS spectrum is consistent with the P-HexNAc headgroup reported by Ferrante et al. (1986). (B) IPL-6; mass fragments of 895 and 1056 Da are consistent with PI-AR and Hex(NH₂)-PI-AR (see below); the remaining 68 Da mass loss was attributed to a C₅H₈ group, which was supported by exact mass determination (cf. Table 2). (C,D) IPL-9 and IPL-10; the predicted elemental formula indicated that the 161 Da loss of IPL-9 was likely a hexose substituted with an amino group [i.e., hexoseamine; Hex(NH₂)], whereas IPL-10 contained a hydroxylated hexose moiety (Hex). (E) IPL-11; the 1056 Da daughter fragment is consistent with that of IPL-9 and the loss of a PI moiety. The elemental formula determined after exact mass determination the presence of 1 N atom and 2 P atoms in this IPL.