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High-resolution crystal structures of the botulinum neurotoxin binding domains from subtypes A5 and A6.

ABSTRACT: Clostridium botulinum neurotoxins (BoNTs) cause flaccid paralysis through inhibition of acetylcholine release from motor neurons; however, at tiny doses, this property is exploited for use as a therapeutic. Each member of the BoNT family of proteins consists of three distinct domains: a binding domain that targets neuronal cell membranes (HC ), a translocation domain (HN ) and a catalytic domain (LC). Here, we present high-resolution crystal structures of the binding domains of BoNT subtypes/A5 (HC /A5) and/A6 (HC /A6). These structures show that the core fold identified in other subtypes is maintained, but with subtle differences at the expected receptor-binding sites.

SUBMITTER: Davies JR

PROVIDER: S-EPMC7396429 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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High-resolution crystal structures of the botulinum neurotoxin binding domains from subtypes A5 and A6.

Davies Jonathan R JR Britton Amy A Liu Sai Man SM Acharya K Ravi KR

FEBS open bio 20200723 8

Clostridium botulinum neurotoxins (BoNTs) cause flaccid paralysis through inhibition of acetylcholine release from motor neurons; however, at tiny doses, this property is exploited for use as a therapeutic. Each member of the BoNT family of proteins consists of three distinct domains: a binding domain that targets neuronal cell membranes (HC ), a translocation domain (HN ) and a catalytic domain (LC). Here, we present high-resolution crystal structures of the binding domain ...[more]

PMID: 32654405

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