Effect of acm deletion on growth of TX82. Shown are growth curves of wild-type E. faecium strain TX82, its nonpolar acm deletion mutant (TX6086), and the previously described acm allelic replacement mutant (TX6051). Cells were grown in BHI broth at 37°C, and aliquots were removed at 0, 2, 4, 6, 9, and 24 h for determination of their CFU counts on BHI agar. Data are representative of two independent experiments.