Related Experiment Video
Updated: Jul 16, 2026
09:51
Purification of a High Molecular Mass Protein in Streptococcus mutans
Published on: September 14, 2019
Comparative genome hybridization of Streptococcus mutans strains
J C Waterhouse1, D C Swan, R R B Russell
1Oral Biology, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK.
Oral Microbiology and Immunology
|February 22, 2007
Summary
Genomic variation in Streptococcus mutans is significant, with 20% of genes absent in some strains. This suggests distinct core and dispensable genomes, explaining bacterial diversity.
Area of Science:
- Microbiology
- Genomics
- Bacterial Genetics
Background:
- Genotypic and phenotypic variation in Streptococcus mutans is not well understood.
- The genome sequence of Streptococcus mutans strain UA159 offers a basis for comparative genomic analysis.
Purpose of the Study:
- To investigate the genomic variation among different strains of Streptococcus mutans.
- To identify absent open reading frames (ORFs) in Streptococcus mutans strains compared to strain UA159.
Main Methods:
- Comparative genomic hybridization using a microarray.
- Microarray probes represented 1948 open reading frames (ORFs) from Streptococcus mutans UA159.
- Genomic DNA from nine Streptococcus mutans strains was used for hybridization.
Main Results:
- 385 (20%) of the UA159 ORFs were absent in at least one of the nine tested strains.
- Absent ORFs often occurred in blocks, including previously identified genomic islands and insertion sequences.
- Approximately half of the absent ORFs likely represent foreign DNA acquired through horizontal gene transfer.
Conclusions:
- The study reveals a distinct core and dispensable genome in Streptococcus mutans.
- Genomic variation, particularly the presence/absence of ORFs, contributes to the phenotypic and genotypic diversity observed in this species.
Related Concept Videos
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...
01:08Evolution 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.