title: Molecular identification key of the family Streptococcaceae.
abstract: The gene order conservation (GOC) between the species of family Streptococcaceae was analysed. The rate of GOC in the strains belonging to the same species is 70% or more. When we compared different species belonging to the same genus, the rate of GOC was 30-47% while it was below 20% when the species were from different genera. A molecular identification key was established for identifying those genera and species within the family Streptococcaceae which have an already known full genome sequence (24 Streptococcus and 2 Lactococcus species). Identical genome parts of the species belonging to the same genus were used for determination of genera. These are the sections surrounding the replication origin dnaA, the sequence from gene phaB to the gene accA, and the sequence of alr acpS secA. Sections around the genes pepX, leuS and rplM were used for identifying the species. The gene order analysis and data in molecular identification key showed that S. uberis and S. parauberis also belong to the same species, and our suggestion for their new names is S. uberis subsp. uberis and S uberis subsp. parauberis. Based on this data, a new definition of bacterial species is proposed: two isolates belong to the same species if the order of the genes in their genomes is almost identical.
authors.affiliation: Nikola Ðurković School Department of Biology Feketić Serbia.
authors.forename: István
authors.initials: I
authors.lastname: Kanyó
authors.affiliation: Nikola Ðurković School Department of Informatics Feketić Serbia.
authors.forename: Dénes
authors.initials: D
authors.lastname: Nagy
mesh_terms: D004269:DNA, Bacterial / Q000032:analysis; D016680:Genome, Bacterial; D009693:Nucleic Acid Hybridization; D013289:Streptococcaceae / Q000145:classification / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial
keywords: Streptococcaceae; bacterial species definition; molecular identification key