Campylobacter hominis sp. nov., from the human gastrointestinal tract

• Published in: International journal of systematic and evolutionary microbiology Vol. 51; no. 2; pp. 651 - 660
• Main Authors: Lawson, AJ, On, SLW, Logan, JMJ, Stanley, J
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01.03.2001; Society for General Microbiology
• Subjects: Bacterial Typing Techniques; Bacteriology; Base Composition; Biological and medical sciences; Campylobacter - classification; Campylobacter - isolation & purification; Campylobacter hominis; Diarrhea - microbiology; DNA, Ribosomal - genetics; Feces - microbiology; Fundamental and applied biological sciences. Psychology; Humans; Intestines - microbiology; Microbiology; Molecular Sequence Data; Nucleic Acid Hybridization; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Phenotype; RNA, Ribosomal, 16S - genetics; rRNA 16S gene; Sequence Analysis, DNA; Systematics; Terminology as Topic; Human; Growth; Campylobacteraceae; Ribosomal DNA; Selectivity; Phylogeny; Infection; Campylobacter infection; Anaerobe; Bacteriosis; 16S-RNA; Bacteria; Isolate; Isolation; Membrane; Strategy; Feces; Campylobacter
• ISSN: 1466-5026; 1466-5034
• DOI: 10.1099/00207713-51-2-651

AJ Lawson, SLW On, JMJ Logan and J Stanley Molecular Biology Unit, Virus Reference Division, Central Public Health Laboratory, 61 Colindale Avenue, London NW9 5HT, UK Sequences of 16S rDNA of a novel campylobacter from faeces of healthy humans were previously shown to originate from a new taxon, 'Candidatus Campylobacter hominis', which could not be cultured. Since phylogenetic analysis suggested that anaerobic conditions might be required for growth, an isolation strategy was developed employing initial non-selective membrane filtration onto fastidious anaerobe agar. Campylobacters were then isolated from the resulting mixed microbial flora by a dilution strategy and/or by immunomagnetic separation with genus-specific polyclonal antibody. Isolates were identified by a genus and taxon-specific PCR assay, and 16S rDNA nucleotide sequence analysis was carried out. All isolates exhibited the typical Campylobacter characteristics of being non-fermentative, oxidase-positive, catalase-negative and Gram-negative. Unusually, however, they were straight rods lacking flagella. The 16S rDNA nucleotide sequence analysis, DNA and mol% G+C were consistent with a new Campylobacter species whose nearest phylogenetic neighbours were Campylobacter gracilis and Campylobacter sputorum. The unique species status of the isolates was further confirmed by taxonomic analysis of 47 phenotypic characteristics. The name Campylobacter hominis sp. nov. is proposed for the new species, the type strain of which is NCTC 13146(T) (=LMG 19568(T)).