Referenced in: none

Automatically associated channels: Kv1.4 , Kv3.1 , Kv4.2

Title: Nanospray analysis of the venom of the tarantula Theraphosa leblondi: a powerful method for direct venom mass fingerprinting and toxin sequencing.

Authors: Christian Legros, Marie-Louise Celerier, Maud Henry, Catherine Guette

Journal, date & volume: Rapid Commun. Mass Spectrom., 2004 , 18, 1024-32

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/15150824

Abstract
Mass spectrometric methods, including matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS), on-line liquid chromatography/electrospray ionisation mass spectrometry (LC/ESI-MS), and nanospray ionisation/hybrid quadrupole time-of-flight mass spectrometry (nanoESI-QqTOFMS), were applied to characterize by mass fingerprinting the venom of the French Guyanese tarantula Theraphosa leblondi. Of these techniques direct nanoESI-QqTOFMS, which allowed the detection of 65 protonated molecules with high mass accuracy, appeared to give the best results. Three major peptides, TlTx1, TlTx2 and TlTx3, were sequenced using a combination of nanoESI-MS/MS and enzyme digestion/MS and MS/MS experiments. Each sequence was confirmed by automated Edman sequencing. In patch-clamp experiments these peptides were found to have a specific inhibitory effect on the voltage-dependent potassium channel, Kv4.2.