51446-64-1Relevant articles and documents
Identification and Composition of Clasper Scent Gland Components of the Butterfly Heliconius erato and Its Relation to Mimicry
Darragh, Kathy,Ehlers, Stephanie,H?tling, Susan,Harig, Tim,Jiggins, Chris D.,Schulz, Stefan,Stell, Matthew,Szczerbowski, Daiane
, p. 3300 - 3313 (2021/10/12)
The butterfly Heliconius erato occurs in various mimetic morphs. The male clasper scent gland releases an anti-aphrodisiac pheromone and additionally contains a complex mixture of up to 350 components, varying between individuals. In 114 samples of five different mimicry groups and their hybrids 750 different compounds were detected by gas chromatography/mass spectrometry (GC/MS). Many unknown components occurred, which were identified using their mass spectra, gas chromatography/infrared spectroscopy (GC/IR)-analyses, derivatization, and synthesis. Key compounds proved to be various esters of 3-oxohexan-1-ol and (Z)-3-hexen-1-ol with (S)-2,3-dihydrofarnesoic acid, accompanied by a large variety of other esters with longer terpene acids, fatty acids, and various alcohols. In addition, linear terpenes with up to seven uniformly connected isoprene units occur, e. g. farnesylfarnesol. A large number of the compounds have not been reported before from nature. Discriminant analyses of principal components of the gland contents showed that the iridescent mimicry group differs strongly from the other, mostly also separated, mimicry groups. Comparison with data from other species indicated that Heliconius recruits different biosynthetic pathways in a species-specific manner for semiochemical formation.
Characterization of the single-subunit oligosaccharyltransferase STT3A from Trypanosoma brucei using synthetic peptides and lipid-linked oligosaccharide analogs
Ramírez, Ana S.,Boilevin, Jérémy,Biswas, Rasomoy,Gan, Bee Ha,Janser, Daniel,Aebi, Markus,Darbre, Tamis,Reymond, Jean-Louis,Locher, Kaspar P.
, p. 525 - 535 (2017/06/09)
The initial transfer of a complex glycan in protein N-glycosylation is catalyzed by oligosaccharyltransferase (OST), which is generally a multisubunit membrane protein complex in the endoplasmic reticulum but a single-subunit enzyme (ssOST) in some protists. To investigate the reaction mechanism of ssOST, we recombinantly expressed, purified and characterized the STT3A protein from Trypanosoma brucei (TbSTT3A). We analyzed the in vitro activity of TbSTT3A by synthesizing fluorescently labeled acceptor peptides as well as lipid-linked oligosaccharide (LLO) analogs containing a chitobiose moiety coupled to oligoprenyl carriers of distinct lengths (C10, C15, C20 and C25) and with different double bond stereochemistry. We found that in addition to proline, charged residues at the +1 position of the sequon inhibited glycan transfer. An acidic residue at the -2 position significantly increased catalytic turnover but was not essential, in contrast to the bacterial OST. While all synthetic LLO analogs were processed by TbSTT3A, the length of the polyprenyl tail, but not the stereochemistry of the double bonds, determined their apparent affinity. We also synthesized phosphonate analogs of the LLOs, which were found to be competitive inhibitors of the reaction, although with lower apparent affinity to TbSTT3A than the active pyrophosphate analogs.
Analysis of the labial gland secretion of the cuckoo-bumblebee (Psithyrus vestalis) males and synthesis of abundant geranylcitronellol
Valterova, Irena,Svatos, Ales,Hovorka, Oldrich
, p. 1501 - 1508 (2007/10/03)
Labial glands of the cuckoo-bumblebee males of the species Psithyrus vestalis were extracted and the components of their secretions were identified. Chemical composition of the males' signal of Psithyrus vestalis has not yet been described in the literatu
