Elucidation of the unexplored biodiversity of ant venom peptidomes via MALDI-TOF mass spectrometry and its application for chemotaxonomy.
The rise of integrative taxonomy, a multi-criteria approach used in characterizing species, fosters the development of new tools facilitating species delimitation. Mass spectrometric (MS) analysis of venom peptides from venomous animals has previously been demonstrated to be a valid method for identifying species. Here we aimed to develop a rapid chemotaxonomic tool for identifying ants based on venom peptide mass fingerprinting. The study focused on the biodiversity of ponerine ants (Hymenoptera: Formicidae: Ponerinae) in French Guiana. Initial experiments optimized the use of automated matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to determine variations in the mass profiles of ant venoms using several MALDI matrices and additives. Data were then analyzed via a hierarchical cluster analysis to classify the venoms of 17 ant species. In addition, phylogenetic relationships were assessed and were highly correlated with methods using DNA sequencing of the mitochondrial gene cytochrome c oxidase subunit 1. By combining a molecular genetics approach with this chemotaxonomic approach, we were able to improve the accuracy of the taxonomic findings to reveal cryptic ant species within species complexes. This chemotaxonomic tool can therefore contribute to more rapid species identification and more accurate taxonomies.


CONCLUSIONS
This is the first extensive study concerning the peptide analysis of the venom of both Pachycondyla and Odontomachus ants. We studied the venoms of 17 ant species from French Guiana that permitted us to fine-tune the venom analysis of ponerine ants via MALDI-TOF mass spectrometry. We explored the peptidomes of crude ant venom and demonstrated that venom peptides can be used in the identification of ant species. In addition, the application of this novel chemotaxonomic method combined with a parallel genetic approach using COI sequencing permitted us to reveal the presence of cryptic ants within both the Pachycondyla apicalis and Pachycondyla stigma species complexes. This adds a new dimension to the search for means of exploiting the enormous biodiversity of venomous ants as a source for novel therapeutic drugs or biopesticides. This article is part of a Special Issue entitled: Proteomics of non-model organisms.
CNRS, UMR Ecologie des Forêts de Guyane (EcoFoG), Campus Agronomique, BP 316, 97379 Kourou Cedex, France. Electronic address: axel.touchard@ecofog.gf.
Axel
A
Touchard
VenomeTech, 473 Route des Dolines - Villa 3, Valbonne 06560, France.
Mélodie
M
Dauvois
VenomeTech, 473 Route des Dolines - Villa 3, Valbonne 06560, France.
Marie-Jeanne
MJ
Arguel
CNRS, UMR Ecologie des Forêts de Guyane (EcoFoG), Campus Agronomique, BP 316, 97379 Kourou Cedex, France.
Frédéric
F
Petitclerc
VenomeTech, 473 Route des Dolines - Villa 3, Valbonne 06560, France.
Mathieu
M
Leblanc
CNRS, UMR Ecologie des Forêts de Guyane (EcoFoG), Campus Agronomique, BP 316, 97379 Kourou Cedex, France; Université de Toulouse, UPS, INP, Laboratoire Écologie Fonctionnelle et Environnement (ECOLAB), 118 route de Narbonne, 31062 Toulouse, France.
Alain
A
Dejean
CNRS, UMR Ecologie des Forêts de Guyane (EcoFoG), Campus Agronomique, BP 316, 97379 Kourou Cedex, France.
Jérôme
J
Orivel
Neurotoxin Research Group, School of Medical & Molecular Biosciences, University of Technology, Sydney, NSW, Australia.
Graham M
GM
Nicholson
VenomeTech, 473 Route des Dolines - Villa 3, Valbonne 06560, France.
Pierre
P
Escoubas
D000818:Animals; D000862:Ant Venoms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001000:Ants / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010449:Peptide Mapping / Q000379:methods*; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
D000862:Ant Venoms; D019476:Insect Proteins; D010455:Peptides
Ant venom; Chemotaxonomy; MALDI–TOF MS; Peptide; Peptidome; Ponerinae