Minimal standards for describing new species belonging to the families Campylobacteraceae and Helicobacteraceae: Campylobacter, Arcobacter, Helicobacter and Wolinella spp

Authors: ON, STEPHEN - LINCOLN UNIVERSITY - NEW ZEALAND; Miller, William - Bill; HOUF, KURT - GHENT UNIVERSITY; FOX, JAMES - MASSACHUSETTS INSTITUTE OF TECHNOLOGY; VANDAMME, PETER - GHENT UNIVERSITY

Submitted to: International Journal of Systematic and Evolutionary Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/24/2017
Publication Date: 10/16/2017
Citation: On, S.L., Miller, W.G., Houf, K., Fox, J.G., Vandamme, P. 2017. Minimal standards for describing new species belonging to the families Campylobacteraceae and Helicobacteraceae: Campylobacter, Arcobacter, Helicobacter and Wolinella spp. International Journal of Systematic and Evolutionary Microbiology. 67:5296-5311. doi:10.1099/ijsem.0.002255.
DOI: https://doi.org/10.1099/ijsem.0.002255

Interpretive Summary: New bacterial species can have either (or sometimes both) agricultural or clinical importance. Thus, it is vitally necessary for such species to be unambiguously defined, with a clearly-delineated set of phenotypic characteristics (for example: tolerance to air, resistance to certain antibiotics, growth on different substrates) that can be used to construct typing methods for both field and clinical use. Moreover, each new species must be clearly separated phenotypically and genotypically (that is, at the DNA sequence level) from related species, to prevent confusion in veterinary and clinical diagnoses. This paper presents a set of minimal standards for use in defining new species within the epsilon subdivision of the Proteobacteria. The standards described in this paper are for those genera within this subdivision that are primarily (but not necessarily exclusively) host-associated, that is Campylobacter, Arcobacter, Helicobacter, and Wolinella. Each species must be distinguishable taxonomically (a complete genome sequence would be strongly recommended), with a unique phenotypic profile. Also, analysis of at least five strains of each new species must be presented to gauge potential species diversity. This paper also recommends approaches for both phenotypic and genotypic characterization of new species.

Technical Abstract: Ongoing changes in taxonomic methods, and in the rapid development of the taxonomic structure of species assigned to the Epsilonproteobacteria have lead the International Committee of Systematic Bacteriology Subcommittee on the Taxonomy of Campylobacter and Related Bacteria to discuss significant updates to previous minimal standards for describing new species of Campylobacteraceae and Helicobacteraceae. This paper is the result of these discussions and proposes minimum requirements for the description of new species belonging to the families Campylobacteraceae and Helicobacteraceae, thus including species in Campylobacter, Arcobacter, Helicobacter, and Wolinella. The core underlying principle remains the use of appropriate phenotypic and genotypic methods to characterise strains sufficiently so as to effectively and unambiguously determine their taxonomic position in these families, and provide adequate means by which the new taxon can be distinguished from extant species and subspecies. This polyphasic taxonomic approach demands the use of appropriate reference data for comparison to ensure the novelty of proposed new taxa, and the recommended study of at least five strains to enable species diversity to be assessed. For free-living species of Arcobacter spp., it is recognised that species may be challenging to isolate and characterise, and that new species may be described using fewer strains but the case for novelty must be compelling. Methodological approaches for phenotypic and genotypic characterisation are recommended.