title: The receptor binding domain of botulinum neurotoxin serotype C binds phosphoinositides.
abstract: Botulinum neurotoxins (BoNTs) are the most toxic proteins known for humans and animals with an extremely low LD(50) of ∼1 ng/kg. BoNTs generally require a protein and a ganglioside on the cell membrane surface for binding, which is known as a "dual receptor" mechanism for host intoxication. Recent studies have suggested that in addition to gangliosides, other membrane lipids such as phosphoinositides may be involved in the interactions with the receptor binding domain (HCR) of BoNTs for better membrane penetration. Using two independent lipid-binding assays, we tested the interactions of BoNT/C-HCR with lipids in vitro domain. BoNT/C-HCR was found to bind negatively charged phospholipids, preferentially phosphoinositides in both assays. Interactions with phosphoinositides may facilitate tighter binding between neuronal membranes and BoNT/C.
authors: Cell Biology and Biochemistry Group, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
authors: Yanfeng
authors: Y
authors: Zhang
authors: Susan M
authors: SM
authors: Varnum
mesh_terms: D001905:Botulinum Toxins / Q000378:metabolism*; D008081:Liposomes; D010716:Phosphatidylinositols / Q000378:metabolism*; D011485:Protein Binding
chemical_list: D008081:Liposomes; D010716:Phosphatidylinositols; D001905:Botulinum Toxins; C096324:botulinum toxin type C