title: Taxonomic relationships of pollens from matrix-assisted laser desorption/ionization time-of-flight mass spectrometry data using multivariate statistics.
abstract: BACKGROUND
  Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been suggested as a promising tool for the investigation of pollen, but the usefulness of this approach for classification and identification of pollen species has to be proven by an application to samples of varying taxonomic relations.
  
  
  METHODS
  MALDI-MS in combination with hierarchical cluster analysis (HCA) and principal component analysis (PCA) was used to delineate taxonomic relations between plants based on pollen biochemistry. To assess the robustness of the approach, pollen of 74 species of the plant orders Fagales and Coniferales were probed.
  
  
  RESULTS
  Discrimination at the levels of plant order and genus were achieved using the whole spectral range. In many cases, different species of the same genus could be distinguished. The sources of the spectral/chemical differences at the genus level can be understood using PCA. Specifically, typical mass regions for exact genus detection were identified.
  
  
  CONCLUSIONS
  Our results indicate that the chemical information represented by MALDI-TOFMS data is useful for reconstructing taxonomic relationships and is complementary to other chemical information on pollen from other spectroscopic data.
authors.affiliation: Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Straße 2, 12489, Berlin, Germany.|BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Straße 11, 12489, Berlin, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Seifert
authors.affiliation: BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Straße 11, 12489, Berlin, Germany.
authors.forename: Steffen M
authors.initials: SM
authors.lastname: Weidner
authors.affiliation: Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Straße 2, 12489, Berlin, Germany.|BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Straße 11, 12489, Berlin, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Panne
authors.affiliation: Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Straße 2, 12489, Berlin, Germany.|BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Straße 11, 12489, Berlin, Germany.
authors.forename: Janina
authors.initials: J
authors.lastname: Kneipp
mesh_terms: D016000:Cluster Analysis; D019684:Magnoliopsida / Q000737:chemistry / Q000145:classification; D015999:Multivariate Analysis; D011058:Pollen / Q000737:chemistry* / Q000145:classification*; D025341:Principal Component Analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*