细胞膜上的欧米茄-3脂肪酸：一个统一的概念

Omega-3 fatty acids in cellular membranes: a unified concept.

细胞膜中的Omega-3脂肪酸：统一的概念。

 

摘要

这里强调了Omega-3脂肪酸DHA（二十二碳六烯酸，22：6）及其姐妹分子EPA（二十碳五烯酸，20：5）。

这些高度不饱和脂肪酸在自然界中广泛存在，特别是在海洋环境中，并且在从深海细菌到人类神经元的膜中是必需的。对细菌中DHA / EPA的研究已经导致了这些分子的结构作用的工作模型，并在本综述中进行了描述。

　

主要观点是：（a）基因组分析显示编码DHA / EPA途径的基因相似，支持细菌中的结构作用可能相似的观点，（b）生化分析表明DHA和EPA是由细菌在细菌中产生的。聚酮化合物过程不同于植物和动物的途径;这使得DHA和EPA可以在厌氧或氧气限制的环境中生产。（c）已经确定并研究了由温度和压力引发的调节系统，并增加了对这些分子作用的理解，（d）DHA / EPA细菌几乎完全位于海洋环境中，提高了膜过程与海洋条件之间重要联系的前景。（e）EPA重组大肠杆菌的生理学研究表明，EPA磷脂为双层提供了必要的流动性，并且富含EPA的膜支持依赖于质子生物能量学的呼吸生活方式; EPA重组体显示可能归因于双层中高水平EPA的其他生理特性，并且（f）化学研究（例如化学动力学建模）支持DHA和可能EPA为膜提供超流体特性的观点。我们假设DHA / EPA磷脂为双层提供流动性和其他性质，从而将这些高度不饱和链与单不饱和物和多不饱和物如18：2和18：3区分开来。我们进一步假设DHA / EPA在细菌中起作用的结构特性也被高等生物利用，以增强关键的膜过程，包括光合作用和能量转导。

　

Abstract

The Omega-3 fatty acid DHA (docosahexaenoic acid, 22:6) and its sister molecule EPA (eicosapentaenoic acid, 20:5) are highlighted here. These highly unsaturated fatty acids are widespread in nature, especially in the marine environment, and are essential in membranes ranging from deep sea bacteria to human neurons. Studies of DHA/EPA in bacteria have led to a working model on the structural roles of these molecules and are described in this review. The main points are: (a) genomic analysis shows that genes encoding the DHA/EPA pathways are similar, supporting the idea that structural roles in bacteria might be similar, (b) biochemical analysis shows that DHA and EPA are produced in bacteria by a polyketide process distinct from the pathway of plants and animals; this allows DHA and EPA to be produced in anaerobic or oxygen-limited environments, (c) regulatory systems triggered by temperature and pressure have been identified and studied, and add to the understanding of the roles of these molecules, (d) DHA/EPA bacteria are located almost exclusively in the marine environment, raising the prospect of an important linkage between membrane processes and marine conditions, (e) physiological studies of an EPA recombinant of E. coli show that EPA phospholipids contribute essential fluidity to the bilayer and that an EPA-enriched membrane supports a respiratory lifestyle dependent on proton bioenergetics; the EPA recombinant displays other physiological properties likely attributed to high levels of EPA in the bilayer, and (f) chemical studies such as chemical dynamic modeling support the idea that DHA and presumably EPA contribute hyperfluidizing properties to the membrane. We hypothesize that DHA/EPA phospholipids contribute fluidity and other properties to the bilayer which distinguish these highly unsaturated chains from monounsaturates and polyunsaturates such as 18:2 and 18:3. We further hypothesize that the structural properties of DHA/EPA functioning in bacteria are also harnessed by higher organisms for enhancing crucial membrane processes including photosynthesis and energy transduction.

　

SOURCE:

PMID: 15458813 DOI: 10.1016/j.plipres.2004.05.004

[Indexed for MEDLINE]

Prog Lipid Res. 2004 Sep;43(5):383-402.

Valentine RC1, Valentine DL.

Author information

Calgene Campus, Monsanto, Inc., Davis, CA 95616, USA. ctomato@davis.com 

Omega-3 fatty acids in cellular membranes: a unified concept. - PubMed - NCBI  https://www.ncbi.nlm.nih.gov/pubmed/15458813