Related Experiment Video
Updated: May 10, 2026
08:03
Heuristic Mining of Hierarchical Genotypes and Accessory Genome Loci in Bacterial Populations
Published on: December 7, 2021
Extensive genomic variation within clonal bacterial groups resulted from homologous recombination
1Department of Biological Sciences; Wayne State University; Detroit, MI USA.
Mobile Genetic Elements
|June 5, 2013
Summary
Genetic variation exists even within identical bacterial clonal groups, challenging traditional views. Understanding this variation, driven by homologous recombination, is key to tracking infectious agent evolution and virulence.
Area of Science:
- Microbiology
- Genetics
- Evolutionary Biology
Background:
- Genetic variation is typically assumed to be low within clonal bacterial groups.
- Recent genome-wide studies indicate significant genetic variation exists even in strains with identical Multilocus Sequence Typing (MLST) types.
- Homologous recombination is a major driver of this observed variation.
Purpose of the Study:
- To investigate and highlight the presence of significant genetic variation within clonal bacterial groups.
- To emphasize the role of homologous recombination in generating this variation.
- To underscore the importance of understanding intra-clonal variation for evolutionary and pathogenicity studies.
Main Methods:
- Genome-wide analyses of bacterial strains.
- Multilocus Sequence Typing (MLST) for clonal group classification.
- Identification and analysis of genetic variation patterns.
Main Results:
- Significant genetic variation was identified in numerous genes among strains with identical MLST types.
- Homologous recombination was confirmed as a primary mechanism introducing genetic variation within these clonal groups.
- This finding challenges the notion of minimal variation within clonal bacterial populations.
Conclusions:
- Bacterial clonal groups harbor substantial genetic variation, contrary to previous assumptions.
- Understanding this variation is crucial for elucidating infectious agent evolution.
- Identifying mechanisms like homologous recombination provides insights into the emergence of pathogenic variants.
Keywords:
homologous recombinationhorizontal gene transfermultilocus sequence typingpathogenic adaptationphylogenomicsprophageMore Related Videos
Related Concept Videos
02:53Conservative Site-specific Recombination and Phase Variation
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
02:08Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
02:08Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
03:21Genome Size and the Evolution of New Genes
While every living organism has a genome of some kind (be it RNA, or DNA), there is considerable variation in the sizes of these blueprints. One major factor that impacts genome size is whether the organism is prokaryotic or eukaryotic. In prokaryotes, the genome contains little to no non-coding sequence, such that genes are tightly clustered in groups or operons sequentially along the chromosome. Conversely, the genes in eukaryotes are punctuated by long stretches of non-coding sequence.
01:08Evolution of Microbial Genome
Microbial genome evolution is a highly dynamic process shaped by continual gene gain and loss across species and strains. This genomic flexibility allows microorganisms to adapt rapidly to environmental pressures and interactions with other organisms. Central to understanding this diversity is the distinction between the core and pan genomes.The core genome comprises the genes shared by all sampled strains of a species, representing essential functions needed for fundamental cellular processes.
00:57Viral Recombination
Cells are sometimes infected by more than one virus at once. When two viruses disassemble to expose their genomes for replication in the same cell, similar regions of their genomes can pair together and exchange sequences in a process called recombination. Alternatively, viruses with segmented genomes can swap segments in a process called reassortment.