40426-22-0Relevant articles and documents
Regulation of mitochondrial ceramide distribution by members of the BCL-2 family
Zhang, Tejia,Barclay, Lauren,Walensky, Loren D.,Saghatelian, Alan
, p. 1501 - 1510 (2015)
Apoptosis is an intricately regulated cellular process that proceeds through different cell type- and signaldependent pathways. In the mitochondrial apoptotic program, mitochondrial outer membrane permeabilization by BCL-2 proteins leads to the release of apoptogenic factors, caspase activation, and cell death. In addition to protein components of the mitochondrial apoptotic machinery, an interesting role for lipids and lipid metabolism in BCL-2 family-regulated apoptosis is also emerging. We used a comparative lipidomics approach to uncover alterations in lipid profi le in the absence of the proapoptotic proteins BAX and BAK in mouse embryonic fi broblasts (MEFs). We detected over 1,000 ions in these experiments and found changes in an ion with an m/z of 534.49. Structural elucidation of this ion through tandem mass spectrometry revealed that this molecule is a ceramide with a 16-carbon N-acyl chain and sphingadiene backbone (d18:2/16:0 ceramide). Targeted LC/MS analysis revealed elevated levels of additional sphingadiene-containing ceramides (d18:2-Cers) in BAX, BAK-double knockout MEFs. Elevated d18:2-Cers are also found in immortalized baby mouse kidney epithelial cells lacking BAX and BAK. These results support the existence of a distinct biochemical pathway for regulating ceramides with different backbone structures and suggest that sphingadiene-containing ceramides may have functions that are distinct from the more common sphingosinecontaining species .
N-Acylated amino acid methyl esters from marine Roseobacter group bacteria
Bruns, Hilke,Ziesche, Lisa,Taniwal, Nargis Khakin,Wolter, Laura,Brinkhoff, Thorsten,Herrmann, Jennifer,Müller, Rolf,Schulz, Stefan
supporting information, p. 2964 - 2973 (2018/12/13)
Bacteria of the Roseobacter group (Rhodobacteraceae) are important members of many marine ecosystems. Similar to other Gram-negative bacteria many roseobacters produce N-acylhomoserine lactones (AHLs) for communication by quorum sensing systems. AHLs regulate different traits like cell differentiation or antibiotic production. Related N-acylalanine methyl esters (NAMEs) have been reported as well, but so far only from Roseovarius tolerans EL-164. While screening various roseobacters isolated from macroalgae we encountered four strains, Roseovarius sp. D12_1.68, Loktanella sp. F13, F14 and D3 that produced new derivatives and analogs of NAMEs, namely N-acyl-2-aminobutyric acid methyl esters (NABME), N-acylglycine methyl esters (NAGME), N-acylvaline methyl esters (NAVME), as well as for the first time a methyl-branched NAME, N-(13-methyltetradecanoyl)alanine methyl ester. These compounds were detected by GC–MS analysis, and structural proposals were derived from the mass spectra and by derivatization. Verification of compound structures was performed by synthesis. NABMEs, NAVMEs and NAGMEs are produced in low amounts only, making mass spectrometry the method of choice for their detection. The analysis of both EI and ESI mass spectra revealed fragmentation patterns helpful for the detection of similar compounds derived from other amino acids. Some of these compounds showed antimicrobial activity. The structural similarity of N-acylated amino acid methyl esters and similar lipophilicity to AHLs might indicate a yet unknown function as signalling compounds in the ecology of these bacteria, although their singular occurrence is in strong contrast to the common occurrence of AHLs. Obviously the structural motif is not restricted to Roseovarius spp. and occurs also in other genera.
N-acylated alanine methyl esters (NAMEs) from Roseovarius tolerans, structural analogs of quorum-sensing autoinducers, N-acylhomoserine lactones
Bruns, Hilke,Thiel, Verena,Voget, Sonja,Patzelt, Diana,Daniel, Rolf,Wagner-Doebler, Irene,Schulz, Stefan
, p. 1559 - 1573 (2013/10/21)
The Roseobacter clade is one of the most important bacteria group living in the ocean. Liquid cultures of Roseovarius tolerans EL 164 were investigated for the production of autoinducers such as N-acylhomoserine lactones (AHLs) and other secondary metabolites. The XAD extracts were analyzed by GC/MS. Two AHLs, Z7-C14: 1-homoserine lactone (HSL) and C15: 1-HSL, were identified. Additionally, the extract contained five compounds with molecular-ion peaks at m/z 104, 145, and 158, thus exhibiting mass spectra similar to those of AHLs with corresponding peaks at m/z 102, 143, and 156. Isolation of the main compound by column chromatography, NMR analysis, dimethyl disulfide derivatization for the determination of the location of the CiC bond and finally synthesis of the compound with the proposed structure confirmed the compound to be (Z)-N-(hexadec-9-enoyl)alanine methyl ester. Four additional minor compounds were identified as C14: 0-, C15: 0-, C16: 0-, and C17: 1-N-acylated alanine methyl esters (NAMEs). All NAMEs have not been described from natural sources before. A BLASTp search showed the presence of AHL-producing luxI genes, but no homologous genes potentially responsible for the structurally closely related NAMEs were found. The involvement of the NAMEs in chemical communication processes of the bacteria is discussed. Copyright
