Abstract
Nine species of uncultivable haemoplasmas and several Mycoplasma species were examined by partial sequencing of two protein-encoding housekeeping genes. Partial glyceraldehyde-3-phosphate dehydrogenase (gapA) and heat shock protein 70 (dnaK) gene sequences were determined for these Mollicute species; in total nine gapA sequences and ten dnaK sequences were obtained. Phylogenetic analyses of these sequences, along with those of a broad selection of Mollicute species downloaded from GenBank, for the individual genes, and for the gapA and dnaK concatenated data set, revealed a clear separation of the haemoplasmas from other species within the Mycoplasma genus; indeed the haemoplasmas resided within a single clade which was phylogenetically detached from the pneumoniae group of Mycoplasmas. This is the first report to examine the use of gapA and dnaK, as well as a concatenated data set, for phylogenetic analysis of the haemoplasmas and other Mollicute species. These results demonstrate a distinct phylogenetic separation between the haemoplasmas and Mycoplasmas that corresponds with the biological differences observed in these species, indicating that further evaluation of the haemoplasmas’ relationship with the Mycoplasma genus is required to determine whether reclassification of the haemoplasmas is necessary.
Highlights
The taxonomic position of the Eperythrozoon and Haemobartonella species has long been a subject of controversy
This is the first report to examine the use of glyceraldehyde-3-phosphate dehydrogenase (gapA) and dnaK for phylogenetic analysis of a wide range of haemoplasmas and other Mollicute species, and the first to describe a concatenated data set for these genes in these species
The samples used in the current study were DNA derived from species obtained for a previous study (Peters et al, 2008): Mycoplasma coccoides, Mycoplasma haemomuris, ‘Candidatus Mycoplasma haemolamae’, ‘Candidatus Mycoplasma kahaneii’, ‘Candidatus Mycoplasma haemocervae’, ‘Candidatus Mycoplasma haematoparvum’, ‘Candidatus Mycoplasma haemohominis’, ‘Candidatus Mycoplasma erythrocervae’, Mycoplasma ovis, Mycoplasma felis, and M. fastidiosum
Summary
The taxonomic position of the Eperythrozoon and Haemobartonella species has long been a subject of controversy. GapA and dnaK are two protein-encoding housekeeping genes that have been previously used in phylogenetic analysis of other bacteria due to their identification as good taxonomic markers (Falah and Grupta, 1997; Fraga et al, 2010; Martens et al, 2008; Wertz et al, 2003) Both gapA and dnaK should provide more resolving power than the 16S rRNA gene and rnpB as they are highly conserved across species but offer higher variation within the sequences than those of rRNA genes, and are well over twice the length of the rnpB gene; gapA and dnaK are approximately 1 Kbp and 1.8 Kbp respectively, in comparison to approximately 0.4 Kbp for rnpB. The continued incorporation of the haemoplasmas within the order Mycoplasmatales family, Incertae sedis highlights the need to further explore the taxonomic position of these bacteria This is the first report to examine the use of gapA and dnaK for phylogenetic analysis of a wide range of haemoplasmas and other Mollicute species, and the first to describe a concatenated data set for these genes in these species
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
