CRSBAN, UFR-SVT-Université de Ouagadougou, BP 7021, Burkina Faso.
Int J Food Microbiol. 2011 Dec 15;151(3):299-306. doi: 10.1016/j.ijfoodmicro.2011.09.022. Epub 2011 Sep 29.
In this study, 67 strains were isolated from two fermented condiments from Burkina Faso: Soumbala and Bikalga. Phenotypical methods, biochemical tests and molecular approaches were used to determinate their genus or species. Twenty-two of them belong to the Bacillus genus. Six strains were selected for their antibacterial or antifungal properties. Their ability to produce lipopeptides synthesized by Non Ribosomal Peptide Synthetases was investigated using two different approaches: PCR with specific degenerated primers and Matrix-assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-ToF MS) performed on whole cells cultivated on a solid medium. PCR revealed that the six strains contain genes involved in the biosynthesis of surfactins whereas surfactins C₁₄ and C₁₅ were only detected by MALDI-ToF MS in two of the six strains. For the first time, the presence of surfactins C₁₄ and C₁₅ was also identified by MALDI-ToF MS analyses directly performed on Soumbala methanolic crude extracts. The structure of these compounds was confirmed by +MS2 and +MS3 of sample and reference surfactins.
在这项研究中,从布基纳法索的两种发酵调味品Soumbala 和 Bikalga 中分离出 67 株菌株。采用表型方法、生化试验和分子方法来确定它们的属或种。其中 22 株属于芽孢杆菌属。选择了 6 株具有抗菌或抗真菌特性的菌株。使用两种不同的方法研究了它们产生非核糖体肽合成酶合成的脂肽的能力:使用特异性简并引物的 PCR 和在固体培养基上培养的全细胞的基质辅助激光解吸电离飞行时间质谱 (MALDI-ToF MS)。PCR 表明,这 6 株菌株含有参与表面活性剂生物合成的基因,而只有通过 MALDI-ToF MS 在其中的 2 株菌株中检测到表面活性剂 C₁₄ 和 C₁₅。通过直接在 Soumbala 甲醇粗提物上进行的 MALDI-ToF MS 分析,首次也鉴定到了表面活性剂 C₁₅ 和 C₁₅的存在。通过对样品和参考表面活性剂的+MS2 和+MS3 对这些化合物的结构进行了确认。