Swainsonine hydrochloride

Cocos nucifera Linn. is a tropical tree grown in various parts of the world. The different parts of Cocos nucifera are used for food and medicinal purposes. This work aimed to determine and characterize the phytoconstituents in the aqueous extracts of Cocos nucifera flowers. The fresh flowers of Cocos nucifera Linn. were collected from southern India. The aqueous extraction of the plant material and the identification and characterization of plant material were performed. 39 compounds were identified and characterized by Liquid-chromatography mass-spectrometry. The major compounds were Nicotiflorin, Myristoyl glycerol, Glucofrangulin B, Valiolone Swainsonine, etc. These bioactive compounds in the Cocos nucifera contribute to the pharmacological activities and this can have the promising prospect in drug development.

N-glycans with complex core chitobiose modifications are observed in various free-living and parasitic nematodes but are absent in mammals. Using Caenorhabditis elegans as a model, we demonstrated that the core N-acetylglucosamine (GlcNAc) residues are modified by three fucosyltransferases (FUTs), namely FUT-1, FUT-6, and FUT-8. Interestingly, FUT-6 can only fucosylate N-glycans lacking the α1,6-mannose upper arm, indicating that a specific α-mannosidase is required to generate substrates for subsequent FUT-6 activity. By analyzing the N-glycomes of aman-3 KOs using offline HPLC-MALDI-TOF MS/MS, we observed that the absence of aman-3 abolishes α1,3-fucosylation of the distal GlcNAc of N-glycans, which suggests that AMAN-3 is the relevant mannosidase on whose action FUT-6 depends. Enzymatic characterization of recombinant AMAN-3 and confocal microscopy studies using a knock-in strain (aman-3::eGFP) demonstrated a Golgi localization. In contrast to the classical Golgi α-mannosidase II (AMAN-2), AMAN-3 displayed a cobalt-dependent α1,6-mannosidase activity toward N-glycans. Using AMAN-3 and other C. elegans glycoenzymes, we were able to mimic nematode N-glycan biosynthesis in vitro by remodeling a fluorescein conjugated-glycan and generate a tri-fucosylated structure. In addition, using a high-content computer-assisted C. elegans analysis platform, we observed that aman-3 deficient worms display significant developmental delays, morphological, and behavioral alterations in comparison to the WT. Our data demonstrated that AMAN-3 is a Golgi α-mannosidase required for core fucosylation of the distal GlcNAc of N-glycans. This enzyme is essential for the formation of the unusual tri-fucosylated chitobiose modifications in nematodes, which may play important roles in nematode development and behavior.