Fig. 6: Lipidomic profiles of archaeal lipids from environmental samples identified using ArchLips database.

A Relative abundance of archaeal lipid classes, (B) Clustering analysis using Euclidean distance and Ward.D method, (C) PCA analysis and (D) Shannon diversity of archaeal lipids. AMD, acid mine drainage (n = 10): AHTL and FK represent samples collected from Tongling and Fankou AMD, respectively. Hot springs (n = 6): hot spring sediment samples collected from Tengchong (GMQ and DRTY). Marine sediment (n = 20): cold seep sediment collected from the South China Sea (ROV01), a sediment core from Pearl River estuaries (GSD) and surface sediment samples from the East China Sea (ESC). Soils (n = 16): soil samples collected from the western region of Sichuan Province (CX) and a sample from Wuhan (YJS), and samples from Qinghai-Tibetan plateau permafrost (NMCVI and LR). The horizontal black lines indicate medians, the box edges represent the interquartile range (25–75th percentiles), and whiskers show the range within 1.5 times the interquartile range. p-values were calculated using two-sided Wilcoxon rank-sum tests. The “*” indicates the significance level of p < 0.05,“**” indicates the significance level of p < 0.01, and “***” indicates the significance level of p < 0.001. Note: the relative abundances reported do not reflect the true relative abundances of lipids in the samples due to the ionization efficiencies of different lipid classes could not be determined.