Kerstersia gyiorum gen. nov., sp. nov., a novel Alcaligenes faecalis-like organism isolated from human clinical samples, and reclassification of Alcaligenes denitrificans Ruger and Tan 1983 as Achromobacter denitrificans comb. nov

1 Laboratorium voor Microbiologie, Universiteit Gent, Gent, Belgium 2 BCCM/LMG Bacteria Collection, Universiteit Gent, Gent, Belgium 3 Culture Collection, Department of Clinical Bacteriology, University of Göteborg, Göteborg, Sweden Correspondence Tom Coenye Tom.Coenye{at}UGent.be A polyphasic taxonomic study was performed on nine isolates recovered from various human clinical samples. Phenotypically, these isolates resembled Alcaligenes faecalis . Whole-cell protein analysis distinguished two different species, and this was confirmed by DNA–DNA hybridizations. Cellular fatty acid analysis and 16S rDNA sequence analysis indicated that these isolates were related to the genera Alcaligenes , Bordetella , Achromobacter and Pigmentiphaga and belonged to the family Alcaligenaceae . On the basis of the results of this study, the organisms were classified in a novel genus, Kerstersia gen. nov. This genus comprises one species, Kerstersia gyiorum sp. nov. (type strain LMG 5906 T =API 184-2-84 T =CCUG 47000 T ), and several unnamed isolates. The DNA G+C content of members of the genus Kerstersia is between 61·5 and 62·9 mol%. On the basis of previously published DNA–DNA hybridization results and data from chemotaxonomic studies, it is proposed that Alcaligenes denitrificans Rüger and Tan 1983 be reclassified as Achromobacter denitrificans comb. nov. The GenBank accession numbers for the 16S rRNA gene sequences of strains LMG 5890 and LMG 5906 T are respectively AY131212 and AY131213 . Protein profiles of the Kerstersia strains, fatty acid compositions of the strains studied and MIC values of the Kerstersia strains are available as supplementary material in IJSEM Online.