Fig. 5

The PefCD transporter protects GAS chromosome from heme-mediated damage. Cultures of NZ131 (WT), ZE4951 (Mutant), ZE4951/pANKITA5b (Complement), and ZE45/pKSM201 (Empty vector) strains were treated with 5 μM heme during the mid logarithmic phase of growth (60–70 Klett units). Genomic DNA was extracted from samples collected at 0, 30 and 90 min post exposure was allowed to react with ARP-biotin and analyzed. The sample absorption at 650 nm was determined and AP site formation was calculated using the standard curve shown in A. All samples were standardized with respect to cell number. The data are derived from two independent experiments each done in triplicates. The asterisk (*) denotes that the observed P value is statistically significant (P < 0.05) and is calculated using student t-test (equal variance) at 0.05 levels of significance