{"title":"Detection of 2-hydroxy-fatty acids and 2-hydroxy-fatty acid-containing ceramides in a gliding marine bacterium Aureispira marina.","authors":"Kazuyoshi Kawahara, Hirokazu Iida, Akira Yokota","doi":"10.2323/jgam.2020.08.002","DOIUrl":null,"url":null,"abstract":"<p><p>The cellular fatty acid composition of Aureispira marina IAM 15389<sup>T</sup> (JCM 23197<sup>T</sup>), a gliding bacterium isolated from the coastline of Thailand, was re-examined by using a standard MIDI method based on alkaline hydrolysis, and two other methods. The direct transesterification using 5% HCl/methanol or 4 M HCl hydrolysis followed by methyl esterification revealed that 2-hydroxy-15-methyl-hexadecanoic acid (2-OH-iso-C<sub>17:0</sub>) and 2-hydroxy-15-methyl-hexadecenoic acid (2-OH-iso-C<sub>17:1</sub>), which were not reported in a previous paper, were found to be major cellular fatty acids of this bacterium, and the amount of 2-OH-iso-C<sub>17:1</sub> was even higher than that of arachidonic acid (C<sub>20:4</sub>), a characteristic polyunsaturated fatty acid present in this bacterium. These 2-hydroxy-fatty acids were contained in two cellular lipids that were relatively stable against alkaline hydrolysis. One of them was analyzed by mass spectrometry, <sup>1</sup>H-nuclear magnetic resonance, and other chemical methods, and identified as a ceramide composed of 2-hydroxy-fatty acid and sphingosine of 19 carbons with three double bonds. A minor ceramide containing 18 carbon sphingosine with three double bonds was also detected.</p>","PeriodicalId":15842,"journal":{"name":"Journal of General and Applied Microbiology","volume":null,"pages":null},"PeriodicalIF":0.8000,"publicationDate":"2021-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of General and Applied Microbiology","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.2323/jgam.2020.08.002","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2021/3/13 0:00:00","PubModel":"Epub","JCR":"Q4","JCRName":"BIOTECHNOLOGY & APPLIED MICROBIOLOGY","Score":null,"Total":0}
引用次数: 1
Abstract
The cellular fatty acid composition of Aureispira marina IAM 15389T (JCM 23197T), a gliding bacterium isolated from the coastline of Thailand, was re-examined by using a standard MIDI method based on alkaline hydrolysis, and two other methods. The direct transesterification using 5% HCl/methanol or 4 M HCl hydrolysis followed by methyl esterification revealed that 2-hydroxy-15-methyl-hexadecanoic acid (2-OH-iso-C17:0) and 2-hydroxy-15-methyl-hexadecenoic acid (2-OH-iso-C17:1), which were not reported in a previous paper, were found to be major cellular fatty acids of this bacterium, and the amount of 2-OH-iso-C17:1 was even higher than that of arachidonic acid (C20:4), a characteristic polyunsaturated fatty acid present in this bacterium. These 2-hydroxy-fatty acids were contained in two cellular lipids that were relatively stable against alkaline hydrolysis. One of them was analyzed by mass spectrometry, 1H-nuclear magnetic resonance, and other chemical methods, and identified as a ceramide composed of 2-hydroxy-fatty acid and sphingosine of 19 carbons with three double bonds. A minor ceramide containing 18 carbon sphingosine with three double bonds was also detected.
采用一种基于碱性水解的标准MIDI法和另外两种方法,对分离自泰国海岸线的滑翔细菌Aureispira marina IAM 15389T (JCM 23197T)的细胞脂肪酸组成进行了重新检测。采用5% HCl/甲醇直接酯交换反应或4 M HCl水解后进行甲基酯化反应,发现2-羟基-15-甲基-十六烯酸(2-OH-iso-C17:0)和2-羟基-15-甲基-十六烯酸(2-OH-iso-C17:1)是该细菌的主要细胞脂肪酸,且2-OH-iso-C17:1的含量甚至高于花生四烯酸(C20:4)。多不饱和脂肪酸这种细菌中特有的多不饱和脂肪酸这些2-羟基脂肪酸包含在两种抗碱性水解相对稳定的细胞脂质中。其中一种经质谱、1h核磁共振等化学方法分析,鉴定为由2-羟基脂肪酸和鞘氨醇组成的神经酰胺,共19个碳,有3个双键。还检测到一种含有18碳鞘氨醇和3个双键的小神经酰胺。
期刊介绍:
JGAM is going to publish scientific reports containing novel and significant microbiological findings, which are mainly devoted to the following categories: Antibiotics and Secondary Metabolites; Biotechnology and Metabolic Engineering; Developmental Microbiology; Environmental Microbiology and Bioremediation; Enzymology; Eukaryotic Microbiology; Evolution and Phylogenetics; Genome Integrity and Plasticity; Microalgae and Photosynthesis; Microbiology for Food; Molecular Genetics; Physiology and Cell Surface; Synthetic and Systems Microbiology.