title: Updating the taxonomic toolbox: classification of Alteromonas spp. using multilocus phylogenetic analysis and MALDI-TOF mass spectrometry.
abstract: Bacteria of the genus Alteromonas are Gram-negative, strictly aerobic, motile, heterotrophic marine bacteria known for their versatile metabolic activities. Identification and classification of novel species belonging to the genus Alteromonas generally involves DNA-DNA hybridization (DDH) as distinct species often fail to be resolved at the 97 % threshold value of the 16S rRNA gene sequence similarity. In this study, the applicability of Multilocus Phylogenetic Analysis (MLPA) and Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for the differentiation of Alteromonas species has been evaluated. Phylogenetic analysis incorporating five house-keeping genes (dnaK, sucC, rpoB, gyrB, and rpoD) revealed a threshold value of 98.9 % that could be considered as the species cut-off value for the delineation of Alteromonas spp. MALDI-TOF MS data analysis reconfirmed the Alteromonas species clustering. MLPA and MALDI-TOF MS both generated data that were comparable to that of the 16S rRNA gene sequence analysis and may be considered as useful complementary techniques for the description of new Alteromonas species.
authors.affiliation: Faculty of Life and Social Sciences, Swinburne University of Technology, PO Box 218, Hawthorn, Vic 3122, Australia.
authors.forename: Hooi Jun
authors.initials: HJ
authors.lastname: Ng
authors.forename: Hayden K
authors.initials: HK
authors.lastname: Webb
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Crawford
authors.forename: François
authors.initials: F
authors.lastname: Malherbe
authors.forename: Henry
authors.initials: H
authors.lastname: Butt
authors.forename: Rachel
authors.initials: R
authors.lastname: Knight
authors.forename: Valery V
authors.initials: VV
authors.lastname: Mikhailov
authors.forename: Elena P
authors.initials: EP
authors.lastname: Ivanova
mesh_terms: D020591:Alteromonas / Q000737:chemistry / Q000145:classification* / Q000235:genetics*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry* / Q000235:genetics*; D020043:Genes, Essential; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S