1
|
Kostygov AY, Butenko A, Nenarokova A, Tashyreva D, Flegontov P, Lukeš J, Yurchenko V. Genome of Ca. Pandoraea novymonadis, an Endosymbiotic Bacterium of the Trypanosomatid Novymonas esmeraldas. Front Microbiol 2017; 8:1940. [PMID: 29046673 PMCID: PMC5632650 DOI: 10.3389/fmicb.2017.01940] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 09/21/2017] [Indexed: 12/22/2022] Open
Abstract
We have sequenced, annotated, and analyzed the genome of Ca. Pandoraea novymonadis, a recently described bacterial endosymbiont of the trypanosomatid Novymonas esmeraldas. When compared with genomes of its free-living relatives, it has all the hallmarks of the endosymbionts’ genomes, such as significantly reduced size, extensive gene loss, low GC content, numerous gene rearrangements, and low codon usage bias. In addition, Ca. P. novymonadis lacks mobile elements, has a strikingly low number of pseudogenes, and almost all genes are single copied. This suggests that it already passed the intensive period of host adaptation, which still can be observed in the genome of Polynucleobacter necessarius, a certainly recent endosymbiont. Phylogenetically, Ca. P. novymonadis is more related to P. necessarius, an intracytoplasmic bacterium of free-living ciliates, than to Ca. Kinetoplastibacterium spp., the only other known endosymbionts of trypanosomatid flagellates. As judged by the extent of the overall genome reduction and the loss of particular metabolic abilities correlating with the increasing dependence of the symbiont on its host, Ca. P. novymonadis occupies an intermediate position P. necessarius and Ca. Kinetoplastibacterium spp. We conclude that the relationships between Ca. P. novymonadis and N. esmeraldas are well-established, although not as fine-tuned as in the case of Strigomonadinae and their endosymbionts.
Collapse
Affiliation(s)
- Alexei Y Kostygov
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia.,Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia
| | - Anzhelika Butenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia.,Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Czechia
| | - Anna Nenarokova
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Czechia.,Faculty of Sciences, University of South Bohemia, České Budějovice, Czechia
| | - Daria Tashyreva
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Czechia
| | - Pavel Flegontov
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia.,Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Czechia.,Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia
| | - Julius Lukeš
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Czechia.,Faculty of Sciences, University of South Bohemia, České Budějovice, Czechia
| | - Vyacheslav Yurchenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czechia.,Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice, Czechia.,Institute of Environmental Technologies, Faculty of Science, University of Ostrava, Ostrava, Czechia
| |
Collapse
|
2
|
Wald N, Margalit H. Auxiliary tRNAs: large-scale analysis of tRNA genes reveals patterns of tRNA repertoire dynamics. Nucleic Acids Res 2014; 42:6552-66. [PMID: 24782525 PMCID: PMC4041420 DOI: 10.1093/nar/gku245] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Decoding of all codons can be achieved by a subset of tRNAs. In bacteria, certain tRNA species are mandatory, while others are auxiliary and are variably used. It is currently unknown how this variability has evolved and whether it provides an adaptive advantage. Here we shed light on the subset of auxiliary tRNAs, using genomic data from 319 bacteria. By reconstructing the evolution of tRNAs we show that the auxiliary tRNAs are highly dynamic, being frequently gained and lost along the phylogenetic tree, with a clear dominance of loss events for most auxiliary tRNA species. We reveal distinct co-gain and co-loss patterns for subsets of the auxiliary tRNAs, suggesting that they are subjected to the same selection forces. Controlling for phylogenetic dependencies, we find that the usage of these tRNA species is positively correlated with GC content and may derive directly from nucleotide bias or from preference of Watson-Crick codon-anticodon interactions. Our results highlight the highly dynamic nature of these tRNAs and their complicated balance with codon usage.
Collapse
Affiliation(s)
- Naama Wald
- Department of Microbiology and Molecular Genetics, IMRIC, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | - Hanah Margalit
- Department of Microbiology and Molecular Genetics, IMRIC, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91120, Israel
| |
Collapse
|