An unprecedented binding mode of vitamin B12 in the predicted transporter BtuM
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Q Exactive
ORGANISM(S): Thiobacillus Denitrificans Atcc 25259
SUBMITTER: 
Stephan Rempel
LAB HEAD: Dirk Jan Slotboom
PROVIDER: PXD010024 | Pride | 2018-10-18
REPOSITORIES: Pride
Publications
Cysteine-mediated decyanation of vitamin B12 by the predicted membrane transporter BtuM.
Rempel S S Colucci E E de Gier J W JW Guskov A A Slotboom D J DJ
Nature communications 20180802 1
Uptake of vitamin B12 is essential for many prokaryotes, but in most cases the membrane proteins involved are yet to be identified. We present the biochemical characterization and high-resolution crystal structure of BtuM, a predicted bacterial vitamin B12 uptake system. BtuM binds vitamin B12 in its base-off conformation, with a cysteine residue as axial ligand of the corrin cobalt ion. Spectroscopic analysis indicates that the unusual thiolate coordination allows for decyanation of vitamin B12 ...[more]
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