Related Experiment Video
Updated: Jul 11, 2026
08:11
Adaptation at the Extremes of Life: Experimental Evolution with the Extremophile Archaeon Sulfolobus acidocaldarius
Published on: June 14, 2024
Variation in gene content among geographically diverse Sulfolobus isolates
Dennis W Grogan1, Melissa A Ozarzak, Rolf Bernander
1Department of Biological Sciences, University of Cincinnati, Cincinnati, OH 45221-0006, USA. grogandw@email.uc.edu
Environmental Microbiology
|September 14, 2007
Summary
Comparative genomic hybridization (CGH) reveals microbial genome diversification in Sulfolobus populations. Increasing geographic distance correlates with genomic differences, supporting an isolation-by-distance model for prokaryotic evolution.
Area of Science:
- Microbial genomics
- Population genetics
- Archaea evolution
Background:
- Comparative genomic hybridization (CGH) can assess microbial genome similarity.
- Previous studies showed Sulfolobus populations diversify along geographical lines.
Purpose of the Study:
- To measure genome relatedness in Sulfolobus populations using CGH.
- To investigate the correlation between spatial separation and genomic diversification.
Main Methods:
- CGH was used to compare eight Sulfolobus isolates against a reference strain.
- 232 polymorphic loci were identified and assigned binary genotypes.
- Clustering analysis was performed on binary genotypes to assess relatedness.
Main Results:
- Genomic clustering was stable and largely consistent with an isolation-by-distance model.
- Spatial separation correlated with both sequence polymorphisms and regions of difference (RDs).
- RDs between conspecific genomes were found to be influenced by geographic distance.
Conclusions:
- CGH effectively reveals genomic diversification patterns in prokaryotes.
- Geographic isolation drives genomic divergence, including RDs, in Sulfolobus.
- CGH is a valuable tool for studying diversification in free-living archaea and bacteria.
Related Concept Videos
02:05Gene Evolution - Fast or Slow?
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
02:54Evolutionary Relationships through Genome Comparisons
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
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.
01:29Modern Molecular Taxonomy
Advancements in molecular biology have revolutionized the identification and characterization of bacteria, with multiple methods leveraging DNA sequencing for enhanced precision. As sequencing technologies improve and costs decline, these approaches are increasingly used in clinical, environmental, and evolutionary studies.Multilocus Sequence Typing (MLST) examines several housekeeping genes, essential chromosomal genes encoding cellular functions, to distinguish strains. Approximately...
01:25Genetic Variation
Genetic variation is the diversity in DNA sequences found among individuals of the same species. This diversity is crucial for a species' survival because it helps organisms adapt to environmental changes. Genetic variation begins with fertilization, where an egg and sperm cell merge. Each of these cells carries 23 chromosomes, up to 46 in the fertilized egg. Chromosomes are long DNA strands that contain genes, the basic units of heredity.
Genes exist in different versions called alleles, which...
Genes exist in different versions called alleles, which...
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.