title: Proteomic-based biotyping reveals hidden diversity within a microalgae culture collection: An example using Dunaliella.
abstract: Accurate and defendable taxonomic identification of microalgae strains is vital for culture collections, industry and academia; particularly when addressing issues of intellectual property. We demonstrate the remarkable effectiveness of Matrix Assisted Laser Desorption Ionisation Time of Flight Mass Spectrometry (MALDI-TOF-MS) biotyping to deliver rapid and accurate strain separation, even in situations where standard molecular tools prove ineffective. Highly distinctive MALDI spectra were obtained for thirty two biotechnologically interesting Dunaliella strains plus strains of Arthrospira, Chlorella, Isochrysis, Tetraselmis and a range of culturable co-occurring bacteria. Spectra were directly compared with genomic DNA sequences (internal transcribed spacer, ITS). Within individual Dunaliella isolates MALDI discriminated between strains with identical ITS sequences, thereby emphasising and enhancing knowledge of the diversity within microalgae culture collections. Further, MALDI spectra did not vary with culture age or growth stage during the course of the experiment; therefore MALDI presents stable and accurate strain-specific signature spectra. Bacterial contamination did not affect MALDI's discriminating power. Biotyping by MALDI-TOF-MS will prove effective in situations wherein precise strain identification is vital, for example in cases involving intellectual property disputes and in monitoring and safeguarding biosecurity. MALDI should be accepted as a biotyping tool to complement and enhance standard molecular taxonomy for microalgae.
authors.affiliation: School of Marine Science and Technology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
authors.forename: Kaveh
authors.initials: K
authors.lastname: Emami
authors.affiliation: School of Biology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
authors.forename: Ethan
authors.initials: E
authors.lastname: Hack
authors.affiliation: Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST.
authors.forename: Andrew
authors.initials: A
authors.lastname: Nelson
authors.affiliation: School of Marine Science and Technology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
authors.forename: Chelsea M
authors.initials: CM
authors.lastname: Brain
authors.affiliation: School of Marine Science and Technology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
authors.forename: Fern M
authors.initials: FM
authors.lastname: Lyne
authors.affiliation: Faculty of Science, Agriculture and Engineering (SAgE), Devonshire Building, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Mesbahi
authors.affiliation: Culture Collection of Algae and Protozoa, Scottish Association for Marine Science, Scottish Marine Institute, Oban, Argyll, PA37 1QA, UK.
authors.forename: John G
authors.initials: JG
authors.lastname: Day
authors.affiliation: School of Marine Science and Technology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
authors.forename: Gary S
authors.initials: GS
authors.lastname: Caldwell
mesh_terms: D000460:Chlorophyta / Q000145:classification / Q000235:genetics / Q000378:metabolism; D058086:Microalgae / Q000145:classification / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D040901:Proteomics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D010940:Plant Proteins