Combining ANOVA-PCA with POCHEMON to analyse micro-organism development in a polymicrobial environment.
Geurts BPDepartment of Analytical Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Neerincx AHDepartment of Molecular and Laser Physics, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Bertrand SFaculty of Pharmacy, University of Nantes, EA 2160-Mer Molécules Santé, 9 Rue Bias BP 53508, Nantes-cedex 1 44035, France; School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, CMU - Rue Michel Servet 1, 1211 Geneva 11, Switzerland.
Leemans MADepartment of Analytical Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Postma GJDepartment of Analytical Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Wolfender JLSchool of Pharmaceutical Sciences, University of Geneva, University of Lausanne, CMU - Rue Michel Servet 1, 1211 Geneva 11, Switzerland.
Cristescu SMDepartment of Molecular and Laser Physics, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Buydens LMDepartment of Analytical Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Jansen JJDepartment of Analytical Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands. Electronic address: chemometrics@science.ru.nl.
English
Revealing the biochemistry associated to micro-organismal interspecies interactions is highly relevant for many purposes. Each pathogen has a characteristic metabolic fingerprint that allows identification based on their unique multivariate biochemistry. When pathogen species come into mutual contact, their co-culture will display a chemistry that may be attributed both to mixing of the characteristic chemistries of the mono-cultures and to competition between the pathogens. Therefore, investigating pathogen development in a polymicrobial environment requires dedicated chemometric methods to untangle and focus upon these sources of variation. The multivariate data analysis method Projected Orthogonalised Chemical Encounter Monitoring (POCHEMON) is dedicated to highlight metabolites characteristic for the interaction of two micro-organisms in co-culture. However, this approach is currently limited to a single time-point, while development of polymicrobial interactions may be highly dynamic. A well-known multivariate implementation of Analysis of Variance (ANOVA) uses Principal Component Analysis (ANOVA-PCA). This allows the overall dynamics to be separated from the pathogen-specific chemistry to analyse the contributions of both aspects separately. For this reason, we propose to integrate ANOVA-PCA with the POCHEMON approach to disentangle the pathogen dynamics and the specific biochemistry in interspecies interactions. Two complementary case studies show great potential for both liquid and gas chromatography - mass spectrometry to reveal novel information on chemistry specific to interspecies interaction during pathogen development.