GC-content

GC-content is a characteristic of the genome of any given organism. It is the proportion of GC-base pairs in the DNA of the organism. G stands for guanine and C stands for cytosine. GC-pairs in the DNA are connected with three hydrogen bonds instead of two in the AT-pairs (adenine and thymine). This makes the GC-pair stronger and more resistant to denaturation by high temperatures. The GC-content is sometimes used to classify organisms in taxonomy, for example, the ''Actinomycete'' bacteria are characterised as "high GC-content bacteria".