title: Discrimination of different species from the genus Drosophila by intact protein profiling using matrix-assisted laser desorption ionization mass spectrometry.
abstract: BACKGROUND
  The use of molecular biology-based methods for species identification and establishing phylogenetic relationships has supplanted traditional methods relying on morphological characteristics. While PCR-based methods are now the commonly accepted gold standards for these types of analysis, relatively high costs, time-consuming assay development or the need for a priori information about species-specific sequences constitute major limitations. In the present study, we explored the possibility to differentiate between 13 different species from the genus Drosophila via a molecular proteomic approach.
  
  
  RESULTS
  After establishing a simple protein extraction procedure and performing matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) with intact proteins and peptides, we could show that most of the species investigated reproducibly yielded mass spectra that were adequate for species classification. Furthermore, a dendrogram generated by cluster analysis of total protein patterns agrees reasonably well with established phylogenetic relationships.
  
  
  CONCLUSIONS
  Considering the intra- and interspecies similarities and differences between spectra obtained for specimens of closely related Drosophila species, we estimate that species typing of insects and possibly other multicellular organisms by intact protein profiling (IPP) can be established successfully for species that diverged from a common ancestor about 3 million years ago.
authors.affiliation: Department of Dermatology, Venerology and Allergology, Medical Faculty of the Leipzig University, Leipzig, Germany. ralph.feltens@ufz.de
authors.forename: Ralph
authors.initials: R
authors.lastname: Feltens
authors.forename: Renate
authors.initials: R
authors.lastname: Görner
authors.forename: Stefan
authors.initials: S
authors.lastname: Kalkhof
authors.forename: Helke
authors.initials: H
authors.lastname: Gröger-Arndt
authors.forename: Martin
authors.initials: M
authors.lastname: von Bergen
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D004330:Drosophila / Q000235:genetics*; D019143:Evolution, Molecular; D005260:Female; D019476:Insect Proteins / Q000235:genetics; D008297:Male; D010802:Phylogeny; D025341:Principal Component Analysis; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry
chemical_list: D019476:Insect Proteins