%0 Journal Article %T Liquid chromatography/mass spectrometry for the identification and quantification of rhamnolipids. %+ Institut Armand Frappier (INRS-IAF) %A Abdel-Mawgoud, Ahmad Mohammad %A Lépine, François %A Déziel, Eric %< avec comité de lecture %@ 1064-3745 %J Methods in Molecular Biology %I Humana Press/Springer Imprint %V 1149 %P 359-73 %8 2013-11-30 %D 2013 %R 10.1007/978-1-4939-0473-0_30 %M 24818920 %K HPLC %K Reversed phase %K Tandem mass spectrometry %K Electrospray negative ionization %K Rhamnolipids %K Congeners %K HAA %K 13C-labeled RL %K Identification %K Quantification %Z Life Sciences [q-bio] %Z Life Sciences [q-bio]/Microbiology and Parasitology/BacteriologyJournal articles %X Rhamnolipids (RL) are surface-active glycolipids produced by Pseudomonas aeruginosa. They are always produced by this bacterium as a complex mixture of congeners, each composed of one or two rhamnose molecules linked to a dimer of 3-hydroxyfatty acids with a chain length of 8-12 carbons. Increasing interest for RL drives the need for efficient analytical methods to characterize these mixtures of molecules. High-performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (MS/MS) is a very precise and relatively high-throughput method for the identification of each congener and their quantification in bacterial cultures. Using (13)C-labeled RL as internal standards can further enhance the precision of the quantification. Collision-induced dissociation (CID) experiments by MS/MS is a powerful tool for the detection and identification of structural variations in RL produced by various Pseudomonas strains or by a specific strain under different culture conditions. CID even allows the discrimination between isomers with subtle structural variations, like Rha-C8-C10 and Rha-C10-C8, which are almost inseparable chromatographically. We are presenting here the detailed protocols for HPLC/MS and HPLC/MS/MS analysis of RL and their lipid precursors, the 3-(3-hydroxyalkanoyloxy)alkanoic acids (HAA), directly in bacterial culture supernatants. %G English %L pasteur-01134344 %U https://riip.hal.science/pasteur-01134344 %~ RIIP %~ INRS-IAF