Fig. 3

Clusters of orthologous groups (COG) of protein-based classification of S. aureus proteins. Using the COG database, 1038 proteins were classified into 20 groups (C-V). Abundant clusters included R: general function with 146 proteins; J: translation with 123 proteins; S: function unknown with 90 proteins; C: energy production and conversion with 87 proteins; and E: amino acid transport and metabolism with 87 proteins