Determination of G + C content of DNA using high-performance liquid chromatography for the identification of staphylococci and micrococci.

The guanine-plus-cytosine (G + C) content of different species of Staphylococcus and Micrococcus was determined by high-performance liquid chromatography. Purified bacterial DNA was hydrolysed by nuclease P1. The nucleotides were separated by chromatography and quantified by measurement of the optical density at 260 nm. The G + C content of staphylococci ranged from 31.5 to 37.9 moles %, and that of micrococci from 68.7 to 75.2. Most of our results were comparable to those obtained with the thermal method.