Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences & Department of Geosciences, University of Bremen, 28359 Bremen, Germany.
Archaea. 2012;2012:832097. doi: 10.1155/2012/832097. Epub 2012 May 14.
Novel cardiolipins from Archaea were detected by screening the intact polar lipid (IPL) composition of microbial communities associated with methane seepage in deep-sea sediments from the Pakistan margin by high-performance liquid chromatography electrospray ionization mass spectrometry. A series of tentatively identified cardiolipin analogues (dimeric phospholipids or bisphosphatidylglycerol, BPG) represented 0.5% to 5% of total archaeal IPLs. These molecules are similar to the recently described cardiolipin analogues with four phytanyl chains from extreme halophilic archaea. It is worth noting that cardiolipin analogues from the seep archaeal communities are composed of four isoprenoidal chains, which may contain differences in chain length (20 and 25 carbon atoms) and degrees of unsaturation and the presence of a hydroxyl group. Two novel diether lipids, structurally related to the BPGs, are described and interpreted as degradation products of archaeal cardiolipin analogues. Since archaeal communities in seep sediments are dominated by anaerobic methanotrophs, our observations have implications for characterizing structural components of archaeal membranes, in which BPGs are presumed to contribute to modulation of cell permeability properties. Whether BPGs facilitate interspecies interaction in syntrophic methanotrophic consortia remains to be tested.
通过高效液相色谱电喷雾电离质谱法筛选与巴基斯坦海域深海沉积物甲烷渗漏相关的微生物群落的完整极性脂质 (IPL) 组成，发现了古菌的新型心磷脂。一系列暂定鉴定的心磷脂类似物（二聚磷脂或双磷脂酰甘油，BPG）占总古菌 IPL 的 0.5%至 5%。这些分子与最近从极端嗜盐古菌中描述的具有四个植烷链的心磷脂类似物相似。值得注意的是，渗漏古菌群落的心磷脂类似物由四个异戊二烯链组成，这些链可能在链长（20 和 25 个碳原子）和不饱和度以及羟基的存在方面存在差异。描述并解释了两种与 BPG 结构相关的新型醚脂，它们被认为是古菌心磷脂类似物的降解产物。由于渗漏沉积物中的古菌群落主要由厌氧甲烷营养菌主导，因此我们的观察结果对于表征古菌膜的结构成分具有重要意义，其中 BPG 被认为有助于调节细胞通透性特性。BPG 是否有助于协同产甲烷菌联合体中的种间相互作用仍有待测试。
