Related Experiment Video
Updated: Sep 21, 2026

DNA Stable-Isotope Probing (DNA-SIP)
Published on: August 2, 2010
The guanine and cytosine content of genomic DNA and bacterial evolution
Abstract:
The genomic guanine and cytosine (G + C) content of eubacteria is related to their phylogeny. The G + C content of various parts of the genome (protein genes, stable RNA genes, and spacers) reveals a positive linear correlation with the G + C content of their genomic DNA. However, the plotted correlation slopes differ among various parts of the genome or among the first, second, and third positions of the codons depending on their functional importance. Facts suggest that biased mutation pressure, called A X T/G X C pressure, has affected whole DNA during evolution so as to determine the genomic G + C content in a given bacterium. The role of A X T/G X C pressure in diversification of bacterial DNA sequences and codon usage patterns is discussed in the perspective of the neutral theory of molecular evolution.
Related Concept Videos
Genomic DNA in Prokaryotes
Genomic Diversity in Bacteria
Although bacterial genomes are much...
Gene Evolution - Fast or Slow?
In contrast, regions which code...
Genome Size and the Evolution of New Genes
Genome Size and the Evolution of New Genes
Gene Evolution - Fast or Slow?
In contrast, regions which code...
Evolution of Microbial Genome

