title: X-ray studies reveal lanthanide binding sites at the A/B5 interface of E. coli heat labile enterotoxin.
abstract: The crystal structure determination of heat labile enterotoxin (LT) bound to two different lanthanide ions, erbium and samarium, revealed two distinct ion binding sites in the interface of the A subunit and the B pentamer of the toxin. One of the interface sites is conserved in the very similar cholera toxin sequence. These sites may be potential calcium binding sites. Erbium and samarium binding causes a change in the structure of LT: a rotation of the A1 subunit of up to two degrees relative to the B pentamer.
authors.affiliation: BIOSON Research Institute, Department of Chemistry, University of Groningen, The Netherlands.
authors.forename: T K
authors.initials: TK
authors.lastname: Sixma
authors.forename: A C
authors.initials: AC
authors.lastname: Terwisscha van Scheltinga
authors.forename: K H
authors.initials: KH
authors.lastname: Kalk
authors.forename: K
authors.initials: K
authors.lastname: Zhou
authors.forename: E S
authors.initials: ES
authors.lastname: Wartna
authors.forename: W G
authors.initials: WG
authors.lastname: Hol
mesh_terms: D001427:Bacterial Toxins / Q000378:metabolism*; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D002412:Cations; D004768:Enterotoxins / Q000378:metabolism*; D004871:Erbium / Q000378:metabolism*; D029968:Escherichia coli Proteins; D011487:Protein Conformation; D012493:Samarium / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D001427:Bacterial Toxins; D002412:Cations; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D012493:Samarium; D004871:Erbium; C027538:heat-labile enterotoxin, E coli; D002118:Calcium