Culture-independent genomic characterisation of Candidatus Chlamydia sanzinia, a novel uncultivated bacterium infecting snakes. (December 2016)

• Record Type: Journal Article
• Authors: Taylor-Brown, Alyce; Bachmann, Nathan; Borel, Nicole; Polkinghorne, Adam
• Is Part Of: BMC genomics. Volume 17:Number 1(2016)
• Page Start: 1
• Page End: 9
• Publication Date: 2016-12
• Subjects: Chlamydia -- Culture-independent sequencing -- Genomics -- Reptile; Genomes -- Periodicals; Gene mapping -- Periodicals; Genomics -- Periodicals; Base Sequence -- Periodicals; Chromosome Mapping -- Periodicals; Genetic Techniques -- Periodicals; Sequence Analysis, DNA -- Periodicals; 572.8605
• DOI: 10.1186/s12864-016-3055-x
• Languages: English
• ISSNs: 1471-2164

Abstract

Abstract Background Recent molecular studies have revealed considerably more diversity in the phylumChlamydiae than was previously thought. Evidence is growing that many of these novel chlamydiae may be important pathogens in humans and animals. A significant barrier to characterising these novel chlamydiae is the requirement for culturing. We recently identified a range of novel uncultured chlamydiae in captive snakes in Switzerland, however, nothing is known about their biology. Using a metagenomics approach, the aim of this study was to characterise the genome of a novel chlamydial taxon from the choana of a captive snake. In doing so, we propose a new candidate species in the genusChlamydia (Candidatus Chlamydia sanzinia) and reveal new information about the biological diversity of this important group of pathogens. Results We identified two chlamydial genomic contigs: a 1, 113, 073 bp contig, and a 7, 504 bp contig, representing the chromosome and plasmid ofCa . Chlamydia sanzinia strain 2742-308, respectively. The 998 predicted coding regions include an expanded repertoire of outer membrane proteins (Pmps and Omps), some of which exhibited frameshift mutations, as well as several chlamydial virulence factors such as the translocating actin-recruitment phosphoprotein (Tarp) and macrophage inhibition potentiator (Mip). A suite of putative inclusion membrane proteins were also predicted. Notably, no evidence of a traditional chlamydial plasticity zone was identified. Phylogenetically, Ca . Chlamydia sanzinia forms a clade withC. pneumoniae andC. pecorum, distinct from former "Chlamydophila " species. Conclusions Genomic characterisation of a novel uncultured chlamydiae from the first reptilian host has expanded our understanding of the diversity and biology of a genus that was thought to be the most well-characterised in this unique phylum. It is anticipated that this method will be suitable for characterisation of other novel chlamydiae.