Investigation of the presence of an aliphatic biopolymer in cyanobacteria: Implications for kerogen formation
Investigation of the presence of an aliphatic biopolymer in cyanobacteria: Implications for kerogen formation
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DOI：
10.1016/j.orggeochem.2015.01.010
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发表时间：
2015-04-01
影响因子：
3
通讯作者：
Skill, Stephen C.
中科院分区：
文献类型：
--
作者：
Biller, Patrick;Ross, Andrew B.;Skill, Stephen C.
阿尔盖南被认为是某些干酪根的主要前体之一。它是一种不能水解、不能溶解的高分子生物大分子。在数量有限的微藻物种中发现了它。关于它的形成和保存，以及它在干酪根形成中的作用和对全球碳循环的影响，存在相当大的不确定性。我们测试了蓝藻Chlorogloeopsis fritschii是否能合成一种类似于藻胶的生物大分子，通过选择性保存对干酪根有贡献。对两种淡水绿藻--椭圆形假轮藻和斜生栅藻以及弗氏绿球藻进行了苛刻的溶剂提取和水解处理，得到了一种不溶于水、不能水解的大分子。利用裂解-气相色谱-质谱仪和固体核磁共振波谱对三种物质的残留物进行了分析。分析表明，绿球藻确实含有一种抗性生物大分子，具有海藻聚糖脂的特征结构，与两种微藻的海藻聚糖残留物相似。由于与真核生物相比，绿球藻具有强大的生命力，它可以在极端环境条件下占优势，如冻结、解冻、干燥和过热--这些条件在原始地球上很普遍。绿球藻中存在一种抗性脂肪族生物聚合物，这表明蓝藻可能通过选择性保存对干酪根做出了贡献。(C)2015年提交人。爱思唯尔有限公司出版。
Algaenan has been suggested to be one of the main precursors of certain kerogens. It is a non-hydrolysable and insoluble biomolecule of high molecular weight. It has been found in a limited number of microalgae species. There is considerable uncertainty about its formation and preservation, as well as its role in kerogen formation and the implications for the global C cycle. We tested whether the cyanobacterium Chlorogloeopsis fritschii can synthesise a biomacromolecule similar to algaenan with potential to contribute to kerogen via selective preservation. Two freshwater green microalgae, Pseudochoricystis ellipsoidea and Scenedesmus obliquus, as well as Chlorogloeopsis fritschii, were subjected to harsh solvent extraction and hydrolysis steps to obtain an insoluble and non-hydrolysable macromolecule. The residues from all three species were analysed using pyrolysis-gas chromatography-mass spectrometry and solid-state nuclear magnetic resonance spectroscopy. The analysis revealed that Chlorogloeopsis fritschii indeed contains a resistant biomacromolecule exhibiting the characteristic aliphatic structure of algaenan, similar to the algaenan residues from the two microalgae. Due to the robust nature of Chlorogloeopsis compared with eukaryotes, it can prevail in extreme environmental conditions such as freezing, thawing, desiccation and overheating - conditions prevalent on the primeval earth. The presence of a resistant aliphatic biopolymer in Chlorogloeopsis suggests that cyanobacteria could have contributed to kerogen via selective preservation. (C) 2015 The Authors. Published by Elsevier Ltd.