Dealkylation of organotin compounds by biological dithiols: toward the chemistry of organotin toxicity.
In this Communication, we report evidence for the dealkylation of trialkyltin compounds by a short linear peptide extracted from a small membrane protein (stannin) involved in cellular apoptosis and containing a CXC motif. We show that (a) organotin binding induces the formation of a beta-turn in the linear peptide, (b) both cysteines are necessary for the dealkylation reaction, and (c) stable 1:1 complexes are formed between the peptide and diorganotins that can be observed by ESI-MS. Organotin degradation by biological dithiols may be responsible for both the delayed activity of these toxins in humans and the organotin resistance mechanisms in bacteria.
Buck
Bethany
B
Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Mascioni
Alessandro
A
Que
Lawrence
L
Veglia
Gianluigi
G
D000478:Alkylation; D002942:Circular Dichroism; D007700:Kinetics; D009479:Neuropeptides / Q000737:chemistry*; D009842:Oligopeptides / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D014001:Tin / Q000737:chemistry*
D009479:Neuropeptides; D009842:Oligopeptides; D009942:Organometallic Compounds; D010446:Peptide Fragments; C075692:stannin; D014001:Tin