Recommended minimal standards for describing new species of the genus Helicobacter.

The International Committee of Systematic Bacteriology Subcommittee on the taxonomy of Campylobacter and related bacteria has agreed in principle on minimum requirements for the description of new species of the genus Helicobacter. These requirements include the recommendation that the description of a putative new species or subspecies be based on examination of at least five strains in order to provide a measure of phenotypic and genotypic variation. Recommendations for required phenotypic and molecular data are presented. The requirements are consistent with the polyphasic approach to bacterial systematics.