The composition and integrity of the bacterial cytoplasmic membrane is critical to the survival of staphylococci in dynamic environments and it is important to investigate how the cell membrane responds to changes in the environmental conditions. The staphylococcal membrane differs from eukaryotic and many other bacterial cell membranes by having a high abundance of branch fatty acids and relatively few unsaturated fatty acids. The range of available methods for extraction and efficient analyses of staphylococcal fatty acids was initially appraised to identify the best potential procedures for appraisal. Staphylococcus aureus subsp. aureus Rosenbach (ATCC® 29213) was grown under optimal conditions to generate a cell biomass to compare the efficiencies of three approaches to extract and prepare methyl esters of the membrane fatty acids: (1) acidic direct transesterification of lipids, (2) modified basic direct transesterification of membrane lipids with adjusted reaction times and temperatures, and (3) base catalysed hydrolysis followed by acid catalysed esterification in two separate chemical reactions (MIDI process). All methods were able to extract fatty acids from the cell mass effectively where these lipids represented approximately 5% of the cellular dry mass. The acidic transesterification method had the least number of steps, the lowest coefficient of variation at 6.7% and good resistance to tolerating water. Basic transesterification was the least accurate method showing the highest coefficient of variation (26%). The MIDI method showed good recoveries, but had twice the number of steps and a coefficient of variation of 16%. It was also found that there was no need to use an anti-oxidant such as BHT for the protection of polyunsaturated fatty acids when the GC–MS injection liner was clean. It was concluded that the acidic transesterification procedures formed the most efficient and reproducible method for the analyses of staphylococcal membrane fatty acids.

细菌细胞质膜的组成和完整性对​​于葡萄球菌在动态环境中的生存至关重要，因此研究细胞膜如何响应环境条件的变化也很重要。金黄色葡萄球菌膜与真核细胞膜和许多其他细菌细胞膜的不同之处在于其分支脂肪酸含量高，不饱和脂肪酸相对较少。最初评估了可用于葡萄球菌脂肪酸提取和有效分析的方法范围，以确定最佳的潜在评估程序。金黄色葡萄球菌亚种。金黄色Rosenbach（ATCC®29213）在最佳条件下生长以产生细胞生物质，以比较三种方法提取和制备膜脂肪酸甲酯的效率：（1）脂质的酸性直接酯交换，（2）改性的碱性直接膜脂质的酯交换反应，反应时间和温度都经过调整，以及（3）碱催化水解，然后在两个独立的化学反应中进行酸催化酯化（MIDI过程）。所有这些方法都能够有效地从细胞团中提取脂肪酸，其中这些脂质约占细胞干物质的5％。酸性酯交换法具有最少的步骤数，最低的变异系数（6.7％）和良好的耐水性。基本的酯交换反应是最不准确的方法，显示出最高的变异系数（26％）。MIDI方法显示出良好的恢复能力，但步骤数增加了一倍，变异系数为16％。还发现，当GC-MS进样口衬管干净时，无需使用抗氧化剂（例如BHT）来保护多不饱和脂肪酸。结论是，酸性酯交换方法形成了最高效，可重复的葡萄球菌膜脂肪酸分析方法。还发现，当GC-MS进样口衬管干净时，无需使用抗氧化剂（例如BHT）来保护多不饱和脂肪酸。结论是，酸性酯交换方法形成了最高效，可重复的葡萄球菌膜脂肪酸分析方法。还发现，当GC-MS进样口衬管干净时，无需使用抗氧化剂（例如BHT）来保护多不饱和脂肪酸。结论是，酸性酯交换方法形成了最高效，可重复的葡萄球菌膜脂肪酸分析方法。