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Meier-Kolthoff, J. P.

Publications and source records attributed to Meier-Kolthoff, J. P..

4 recordsLinked to original sources

Panoramic Insights into the Microevolution and Macroevolution of Prevotella copri-containing Lineage in Primate Guts

Prevotella copri and related taxa are widely detected in mammalian gut microbiomes and have been linked with one human enterotype. However, their microevolution and macroevolution among hosts are poorly characterized. In this study, extensively collected marker genes and genomes were analyzed to trace their evolutionary history, host specificity, and biogeographic distribution. Investigations based on 16S rRNA gene, gyrB, and genomes suggested that a multi-specific P. copri-containing lineage (PCL) harbors diverse species in higher primates. Firstly, P. copri is the dominant species of PCL in the human gut and consists of multiple groups exhibiting high genomic divergence and conspicuous but non-strict biogeographic pattern. Most African strains with high genomic divergence from other strains were phylogenetically placed near the species root, indicating the co-evolutionary history of P. copri and Homo sapiens. Secondly, although long-term co-evolution between PCL and higher primates was revealed, sporadic signals of co-speciation and extensive host jumping of PCL members were observed among higher primates. Metagenomic and phylogenetic analyses indicated that P. copri and other PCL species found in captive mammals have been recently transmitted from humans. Thirdly, strong evidence was found on the extensively horizontal transfer of genes (e.g., carbohydrate-active enzyme encoding genes) among sympatric P. copri groups and PCL species in the same primate host. Our study provides panoramic insights into the complex effects of vertical and horizontal transmission, and potential niche adaption on speciation, host, and biogeographical distribution spanning microevolutionary and macroevolutionary history for a certain gut bacterial lineage. ImportancePrevotella copri and its related taxa, which we designated as Prevotella copri-containing lineage (PCL) in the present study, are widely detected in guts of human, non-human primates and many captive mammals, showing positive or negative correlation to some human diseases. However, a comprehensive understanding on its microevolutionary (within P. copri) and macroevolutionary (among PCL members) history across host species and host biogeography is still lacking. According to our analysis based on 16S rRNA gene, gyrB and genomes, we provided the panoramic insights into the putative effects of vertical transfer, horizontal transmission and potential niche selection on host and biogeographical distribution of this gut bacterial lineage and P. copri. To our knowledge, it is the first time that a gut bacterial lineage was studied at both micro- and macroevolutionary levels, which can aid our systematic understanding on the host-microbe co-evolutionary interactions.

microbiology↗

Comparative genomics unravels mechanisms of genetic adaptation for the catabolism of the phenylurea herbicide linuron in Variovorax

Biodegradation of the phenylurea herbicide linuron appears a specialization within a specific clade of the Variovorax genus. The linuron catabolic ability is likely acquired by horizontal gene transfer but the mechanisms involved are not known. The full genome sequences of six linuron degrading Variovorax strains isolated from geographically distant locations were analyzed to acquire insight in the mechanisms of genetic adaptation towards linuron metabolism in Variovorax. Whole genome sequence analysis confirmed the phylogenetic position of the linuron degraders in a separate clade within Variovorax and indicated their unlikely origin from a common ancestral linuron degrader. The linuron degraders differentiated from non-degraders by the presence of multiple plasmids of 20 to 839 kb, including plasmids of unknown plasmid groups. The linuron catabolic gene clusters showed (i) high conservation and synteny and (ii) strain-dependent distribution among the different plasmids. All were bordered by IS1071 elements forming composite transposon structures appointing IS1071 as key for catabolic gene recruitment. Most of the strain carried at least one broad host range plasmid that might have been a second instrument for catabolic gene acquisition. We conclude that clade 1Variovorax strains, despite their different geographical origin, made use of a limited genetic repertoire to acquire linuron biodegradation.\n\nImportanceThe genus Variovorax and especially a clade of strains that phylogenetically separates from the majority of Variovorax species, appears to be a specialist in the biodegradation of the phenyl urea herbicide linuron. Horizontal gene transfer (HGT) likely played an essential role in the genetic adaptation of those strain to acquire the linuron catabolic genotype. However, we do not know the genetic repertoire involved in this adaptation both regarding catabolic gene functions as well as gene functions that promote HGT neither do we know how this varies between the different strains. These questions are addressed in this paper by analyzing the full genome sequences of six linuron degrading Variovorax strains. This knowledge is important for understanding the mechanisms that steer world-wide genetic adaptation in a particular species and this for a particular phenotypic trait as linuron biodegradation.

microbiology↗

Global genomic population structure of Clostridioides difficile

Clostridioides difficile is the primary infectious cause of antibiotic-associated diarrhea. Local transmissions and international outbreaks of this pathogen have been previously elucidated by bacterial whole-genome sequencing, but comparative genomic analyses at the global scale were hampered by the lack of specific bioinformatic tools. Here we introduce EnteroBase, a publicly accessible database (http://enterobase.warwick.ac.uk) that automatically retrieves and assembles C. difficile short-reads from the public domain, and calls alleles for core-genome multilocus sequence typing (cgMLST). We demonstrate that the identification of highly related genomes is 89% consistent between cgMLST and single-nucleotide polymorphisms. EnteroBase currently contains 13,515 quality-controlled genomes which have been assigned to hierarchical sets of single-linkage clusters by cgMLST distances. Hierarchical clustering can be used to identify populations of C. difficile at all epidemiological levels, from recent transmission chains through to pandemic and endemic strains, and is largely compatible with prior ribotyping. Hierarchical clustering thus enables comparisons to earlier surveillance data and will facilitate communication among researchers, clinicians and public-health officials who are combatting disease caused by C. difficile.

microbiology↗

VICTOR: Genome-based Phylogeny and Classification of Prokaryotic Viruses

Bacterial and archaeal viruses (\"phages\") play an enormous role in global life cycles and have recently regained importance as therapeutic agents to fight serious infections by multi-resistant bacterial strains. Nevertheless, taxonomic classification of phages is up to now only insufficiently informed by genome sequencing. Despite thousands of publicly available phage genomes, it still needs to be investigated how this wealth of information can be used for the fast, universal and accurate classification of phages. The Genome BLAST Distance Phylogeny (GBDP) approach is a truly whole-genome method currently used for in silico DNA: DNA hybridization and phylogenetic inference from prokaryotic genomes. Based on the principles of phylogenetic systematics, we here established GBDP for phage phylogeny and classification, using the common subset of genome-sequenced and officially classified phages. Trees inferred with the best GBDP variants showed only few deviations from the official phage classification, which were uniformly due to incorrectly annotated GenBank entries. Except for low resolution at the family level, the majority of taxa was well supported as monophyletic. Clustering genome sequences with distance thresholds optimized for the agreement with the classification turned out to be phylogenetically reasonable. Accordingly modifying genera and species is taxonomically optional but would yield more uniform sequence divergence as well as stronger branch support. Analysing an expanded data set containing > 4000 phage genomes from public databases allowed for extrapolating regarding the number, composition and host specificity of future phage taxa. The selected methods are implemented in an easy-to-use web service \"VICTOR\" freely available at http://ggdc.dsmz.de/victor.php.

evolutionary biology↗