Frankfater Cheryl F, Sartorio Mariana G, Valguarnera Ezequiel, Feldman Mario F, Hsu Fong-Fu
Mass Spectrometry Resource, Division of Endocrinology, Metabolism, and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States.
Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States.
Biochemistry. 2023 Mar 21;62(6):1160-1180. doi: 10.1021/acs.biochem.2c00664. Epub 2023 Mar 7.
The anaerobic bacteria of the group including , , and in genus are among the most commonly found human gut microbiota. They are generally commensal but are also opportunistic pathogens. Both the inner and outer membranes of the cell envelope contain abundant lipids with diversified structures, and dissection of the lipid composition of the inner and outer membrane fractions is important for understanding the biogenesis of this multilaminate wall structure. Here, we describe mass spectrometry-based approaches to delineate in detail the lipidome of the membrane and the outer membrane vesicle of the bacteria cells. We identified 15 lipid class/subclasses (>100 molecular species), including sphingolipid families [dihydroceramide (DHC), glycylseryl (GS) DHC, DHC-phosphoinositolphosphoryl-DHC (DHC-PIP-DHC), ethanolamine phosphorylceramide, inositol phosphorylceramide (IPC), serine phosphorylceramide, ceramide-1-phosphate, and glycosyl ceramide], phospholipids [phosphatidylethanolamine, phosphatidylinositol (PI), and phosphatidylserine], peptide lipids (GS-, S-, and G-lipids) and cholesterol sulfate, of which several have not been reported previously, or have similar structures to those found in , the periodontopathic bacterium in oral microbiota. The new DHC-PIPs-DHC lipid family is found only in , which, however, lacks the PI lipid family. The galactosyl ceramide family is exclusively present in , which nevertheless lacks IPC and PI lipids. The lipidomes as revealed in this study demonstrate the lipid diversity among the various strains and the utility of multiple-stage mass spectrometry (MS) with high-resolution mass spectrometry in the structural elucidation of complex lipids.
包括属中的、、和在内的该类厌氧菌是人类肠道微生物群中最常见的菌群。它们通常是共生菌，但也是机会致病菌。细胞包膜的内膜和外膜都含有丰富的、结构多样的脂质，剖析内膜和外膜组分的脂质组成对于理解这种多层壁结构的生物发生至关重要。在这里，我们描述了基于质谱的方法，以详细描绘细菌细胞膜和外膜囊泡的脂质组。我们鉴定出15种脂质类别/亚类（>100种分子种类），包括鞘脂家族[二氢神经酰胺（DHC）、甘氨酰丝氨酰（GS）DHC、DHC-磷酸肌醇磷酸化-DHC（DHC-PIP-DHC）、乙醇胺磷酸神经酰胺、肌醇磷酸神经酰胺（IPC）、丝氨酸磷酸神经酰胺、神经酰胺-1-磷酸和糖基神经酰胺]、磷脂[磷脂酰乙醇胺、磷脂酰肌醇（PI）和磷脂酰丝氨酸]、肽脂质（GS-、S-和G-脂质）和硫酸胆固醇，其中几种以前尚未报道过，或者其结构与口腔微生物群中的牙周病原菌中发现的结构相似。新的DHC-PIPs-DHC脂质家族仅在中发现，然而，中缺乏PI脂质家族。半乳糖基神经酰胺家族仅存在于中，不过，中缺乏IPC和PI脂质。本研究揭示的脂质组证明了不同菌株之间的脂质多样性，以及多级质谱（MS）与高分辨率质谱在复杂脂质结构解析中的实用性。
