Evolutionary relationships amongst Chlorobia and Ignavibacteria species/strains were examined using phylogenomic and comparative analyses of genome sequences. In a phylogenomic tree based on 282 conserved proteins, the named Chlorobia species formed a monophyletic clade containing two distinct subclades. One clade, encompassing the genera Chlorobaculum, Chlorobium, Pelodictyon, and Prosthecochloris, corresponds to the family Chlorobiaceae, whereas another clade, harboring Chloroherpeton thalassium, Candidatus Thermochlorobacter aerophilum, Candidatus Thermochlorobacteriaceae bacterium GBChlB, and Chlorobium sp. 445, is now proposed as a new family (Chloroherpetonaceae fam. nov). In parallel, our comparative genomic analyses have identified 47 conserved signature indels (CSIs) in diverse proteins that are exclusively present in members of the class Chlorobia or its two families, providing reliable means for identification. Two known Ignavibacteria species in our phylogenomic tree are found to group within a larger clade containing several Candidatus species and uncultured Chlorobi strains. A CSI in the SecY protein is uniquely shared by the species/strains from this “larger Ignavibacteria clade”. Two additional CSIs, which are commonly shared by Chlorobia species and the “larger Ignavibacteria clade”, support a specific relationship between these two groups. The newly identified molecular markers provide novel tools for genetic and biochemical studies and identification of these organisms.
1
2
3
*
Microorganisms
2022,
10(7), 1312; https://doi.org/10.3390/microorganisms10071312
Keywords:phylogenomic and comparative genomic analyses; conserved signature indels (CSIs); molecular signatures; class
Chlorobiaand the families
Chlorobiaceaeand
Chloroherpetonaceae;
Ignavibacteria; uncultured species/strains related to
Chlorobia/
Ignavibacteria
Figure 1
ZIP-Document (ZIP, 3267 KiB)
MDPI and ACS Style
Bello, S.; Howard-Azzeh, M.; Schellhorn, H.E.; Gupta, R.S. Phylogenomic Analyses and Molecular Signatures Elucidating the Evolutionary Relationships amongst the Chlorobia and Ignavibacteria Species: Robust Demarcation of Two Family-Level Clades within the Order Chlorobiales and Proposal for the Family Chloroherpetonaceae fam. nov. Microorganisms 2022, 10, 1312. https://doi.org/10.3390/microorganisms10071312
AMA Style
Bello S, Howard-Azzeh M, Schellhorn HE, Gupta RS. Phylogenomic Analyses and Molecular Signatures Elucidating the Evolutionary Relationships amongst the Chlorobia and Ignavibacteria Species: Robust Demarcation of Two Family-Level Clades within the Order Chlorobiales and Proposal for the Family Chloroherpetonaceae fam. nov. Microorganisms. 2022; 10(7):1312. https://doi.org/10.3390/microorganisms10071312
Chicago/Turabian Style
Bello, Sarah, Mohammad Howard-Azzeh, Herb E. Schellhorn, and Radhey S. Gupta. 2022. "Phylogenomic Analyses and Molecular Signatures Elucidating the Evolutionary Relationships amongst the Chlorobia and Ignavibacteria Species: Robust Demarcation of Two Family-Level Clades within the Order Chlorobiales and Proposal for the Family Chloroherpetonaceae fam. nov" Microorganisms 10, no. 7: 1312. https://doi.org/10.3390/microorganisms10071312
Find Other Styles