Dataset Information

Marine Roseobacter sulfur amino lipids (SALs) extraction

ABSTRACT: The Roseobacter Clade Bacteria (RCB) play a crucial role in marine ecosystems, particularly Ruegeria pomeroyi, which utilize organosulfur compounds such as 2,3-dihydroxypropanesulfonate (DHPS) and dimethylsulfoniopropionoate (DMSP). Recently, a new class of sulfonolipids, sulfur amino lipids (SALs), was identified in these bacteria, with possible structures proposed by Smith et al. (ISME Journal, 2021, 15, 2440-2453). This study aims to confirm or revise the proposed structures for SAL-656 and SAL-672. Two candidates for SAL-656 and SAL-672 were synthesized, namely 3-acyloxyacylamides of homotaurine and cysteinolic acid, respectively. Tandem mass spectrometry (MS/MS) analysis of synthetic and natural SALs revealed significant discrepancies, leading to the exclusion of proposed structures. Further exploration of lipid extracts from R. pomeroyi identified related lipoforms of SAL-656 and SAL-672, which form two distinct families based on LC-MS/MS and molecular network analysis. While the mass spectrometric data allow exclusion of previously proposed structures and provide insights into acyl groups and headgroups, the complete structures of SAL-656 and SAL-672 remain elusive. Nonetheless, the data are consistent with revised structures based on cysteinolic acid or 3-amino-2-hydroxypropanesulfonic acid wherein both hydroxyl and amino groups are acylated. Our findings reveal the SALs as a group of sulfonolipids that are distinct from more studied classes of sulfonolipids, with implications for understanding their biosynthesis and ecological roles in marine environments.

INSTRUMENT(S): Vanquish UHPLC linked to an Orbitrap Fusion Lumos mass spectrometer (Thermo Fisher Scientific, San Jose, CA, USA)

ORGANISM(S): Ruegeria Pomeroyi Dss-3 (ncbitaxon:246200)

SUBMITTER: Professor Spencer J Williams