Carbohydrate profiles of S. aureus determined by GC-MS. (A) Cells grown in phosphate-rich medium. (B) Cells grown in phosphate-limited medium. Note that the levels of anhydroribitol and fucosamine (markers for teichoic acid and capsule, respectively) are unchanged between the two growth conditions. Other peaks: 1, glycerol; 2, ribose plus ribitol; 3, arabinitol (internal standard); 4, glucose; 5, muramic acid; 6, methylglucamine (internal standard); 7, glucosamine.