Brachyspira catarrhinii sp. nov., an anaerobic intestinal spirochaete isolated from vervet monkeys may have been misidentified as Brachyspira aalborgi in previous studies. (October 2019)

• Record Type: Journal Article
• Authors: Phillips, Nyree D.; La, Tom; Hampson, David J.
• Is Part Of: Anaerobe. Volume 59(2019)
• Page Start: 8
• Page End: 13
• Publication Date: 2019-10
• Subjects: Spirochaete -- Brachyspira catarrhinii sp. nov. -- Non-human primates -- Old world monkeys -- Intestinal spirochaetosis; ANI Average Nucleotide Identity -- bp base pairs -- GGD Genome-Genome Distance -- IS intestinal spirochaetosis -- MLST multilocus sequence typing -- NHP non-human primate -- PCR-RFLP restriction fragment length analysis of PCR products -- SNP single nucleotide polymorphism; Anaerobic infections -- Periodicals; Anaerobic bacteria -- Periodicals; Bacterial diseases -- Periodicals; Computer network resources; Anaerobic protozoa -- Periodicals; 579.3
• DOI: 10.1016/j.anaerobe.2019.05.004
• Languages: English
• ISSNs: 1075-9964

Abstract

Abstract: To date nine species of anaerobic intestinal spirochaetes have been validly assigned to the genus Brachyspira . These include both pathogenic and non-pathogenic species. In the current study a genomic analysis of a novel spirochaete isolate was undertaken to determine whether it is a distinct species that previously has been misidentified as Brachyspira aalborgi . The genome of spirochaete strain Z12 isolated from the faeces of a vervet monkey was sequenced and compared to the genomes of the type strains of the nine assigned Brachyspira species. Genome to Genome Distance (GGD) values and Average Nucleotide Identity (ANI) values were determined. Single nucleotide polymorphisms (SNP) were used to create a phylogenetic tree to assess relatedness. The 16S rRNA gene sequences of the strains were aligned and the similarity amongst the Brachyspira species was recorded. Multilocus sequence typing (MLST) using five loci was conducted on Z12 and results compared with those for other Brachyspira isolates. Assembly of the Z12 sequences revealed a 2, 629, 108 bp genome with an average G + C content of 31.3%. The GGD, ANI, 16S rRNA gene sequence comparisons and the MLST results all indicated that Z12 represents a distinct species within the genus Brachyspira, with its nearest neighbour being B. aalborgi. Spirochaete strain Z12 T was assigned as the type strain of a new species, Brachyspira catarrhinii sp. nov. The diagnostic PCR currently in use to detect B. aalborgi cross-reacts with Z12, but RFLP analysis of PCR product can be used to distinguish the two species. Previous reports of non-human primates being colonised by B. aalborgi based on PCR results may have been incorrect. The development of an improved diagnostic method will allow future studies on the distribution and possible clinical significance of these two anaerobic spirochaete species. Highlights: The genome of an anaerobic intestinal spirochaete isolate from a vervet monkey was characterised. The isolate was shown to represented a new species, proposed as Brachyspira catarrhinii sp. nov. B. catarrhinii cross-reacted in a diagnostic PCR for Brachyspira aalborgi from humans. Previous reports of B. aalborgi being detected in non-human primates may have been incorrect. A PCR-RFLP method was developed to distinguish between B. catarrhinii and B. aalborgi .