Substrate recognition of VAMP-2 by botulinum neurotoxin B and tetanus neurotoxin

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal

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Author(s)

Detail(s)

Original languageEnglish
Pages (from-to)21153-21159
Journal / PublicationJournal of Biological Chemistry
Volume283
Issue number30
Online published29 May 2008
Publication statusPublished - 25 Jul 2008
Externally publishedYes

Abstract

Botulinum neurotoxin (BoNT; serotypes A-G) and tetanus neurotoxin elicit flaccid and spastic paralysis, respectively. These neurotoxins are zinc proteases that cleave SNARE proteins to inhibit synaptic vesicle fusion to the plasma membrane. Although BoNT/B and tetanus neurotoxin (TeNT) cleave VAMP-2 at the same scissile bond, their mechanism(s) of VAMP-2 recognition is not clear. Mapping experiments showed that residues 60-87 of VAMP-2 were sufficient for efficient cleavage by BoNT/B and that residues 40-87 of VAMP-2 were sufficient for efficient TeNT cleavage. Alanine-scanning mutagenesis and kinetic analysis identified three regions within VAMP-2 that were recognized by BoNT/B and TeNT: residues adjacent to the site of scissile bond cleavage (cleavage region) and residues located within N-terminal and C-terminal regions relative to the cleavage region. Analysis of residues within the cleavage region showed that mutations at the P7, P4, P2, and P1′ residues of VAMP-2 had the greatest inhibition of LC/B cleavage (≥32-fold), whereas mutations at P7, P4, P1′, and P2′ residues of VAMP-2 had the greatest inhibition of LC/TeNT cleavage (≥64-fold). Residues within the cleavage region influenced catalysis, whereas residues N-terminal and C-terminal to the cleavage region influenced binding affinity. Thus, BoNT/B and TeNT possess similar organization but have unique residues to recognize and cleave VAMP-2. These studies provide new insights into how the clostridial neurotoxins recognize their substrates.

Citation Format(s)

Substrate recognition of VAMP-2 by botulinum neurotoxin B and tetanus neurotoxin. / Chen, Sheng; Hall, Cherisse; Barbieri, Joseph T.

In: Journal of Biological Chemistry, Vol. 283, No. 30, 25.07.2008, p. 21153-21159.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal