Acid Hydrolysis for the Extraction of Archaeal Core Lipids and HPLC-MS Analysis

Abstract

Lipid membranes are essential cellular elements as they provide cellular integrity and selective permeability under a broad range of environmental settings upon cell growth. In particular, Archaea are commonly recognized for their tolerance to extreme conditions, which is now widely accepted to stem from the unique structure of their lipids. While enhancing the stability of the archaeal cell membrane, the exceptional properties of archaeal lipids also hinder their extraction using regular procedures initially developed for bacterial and eukaryotic lipids. The protocol described here circumvents these issues by directly hydrolyzing the polar head group(s) of archaeal lipids and extracting the resulting core lipids. Although leading to a loss of information on the nature of polar heads, this procedure allows the quantitative extraction of core lipids for most types of archaeal cells in an efficient, reproducible, and rapid manner.

Membrane adaptation in the hyperthermophilic archaeon Pyrococcus furiosus relies upon a novel strategy involving glycerol monoalkyl glycerol tetraether lipids

“…and analysed by high‐performance liquid chromatography‐mass spectrometry using an HP 1100 series HPLC instrument equipped with an auto‐injector and a Chemstation chromatography manager software connected to a Bruker Esquire 3000 Plus ion trap mass spectrometer, as described in Tourte et al . (2021). A standard solution containing core DGD and GDGT0 in a 2/1 M ratio demonstrated a molar response factor of DGD approximately 10 times lower than that of GDGT0 under our analytical conditions.…”