Novel Cardiolipins from Uncultured Methane-Metabolizing Archaea
Figure 1
(a) Photography of the seafloor at site GeoB 12315 (~1000 m water depth) during expedition M74/3 taken by the remotely operated vehicle Quest (MARUM, University of Bremen) in the continental margin off Pakistan; (b) density map plot showing archaeal IPLs (in black), bacterial IPLs (in gray), and novel archaeal lipids (bold) analyzed in positive mode by HPLC-ESI-IT-MS; (c) zoom in the regular BPGs area of a density map generated in positive mode HPLC-ESI-ToF-MS (BPG-1 with four C20, BPG-2 with three C20 and one C25, and BPG-3 with two C20 and two C25); (d) structure of archaeal BPGs, other archaeal cardiolipin analogues, and PGPG-ARs. R1 to R7 are tentatively identified isoprenoidal moieties. Compound Abbreviations. GDGT: glycerol dibiphytanyl glycerol tetraether (C40–C40 isoprenoidal chains); AR: archaeol (C20–C20 isoprenoidal chains); Ext-AR: extended archaeol (C20–C25 isoprenoidal chains); OH-AR: monohydroxylated-archaeol (OHC20–C20); diOH: dihydroxylated-archaeol (OHC20–OHC20); Uns-AR: unsaturated-archaeol; Gly: glycosyl (hexose); PE: phosphatidylethanolamine; PG: phosphatidylglycerol; PI: phosphatidylinositol; PS: phosphatidylserine; Ser: serine.
