FIG 4.
One-step nickel affinity purification of Erm(44)-RGS-His6 from S. aureus RN4220 (A) and E. coli AG100A or AG100 (B). Cells carried one of the erm(44)-rgs-his6 expression vectors (pBJW13-RGS-His, pBJW13-HC-RGS-His, and pTJW13-RGS-His) or the empty pBUS1-Pcap-HC vector as a negative control. Total protein extracts (T) or nickel affinity fractions (Ni) were separated using 15% SDS-PAGE, and the gels were stained with Coomassie brilliant blue. For RN4220, 12 μl of total protein extracts and 30 μl of nickel affinity fractions were analyzed. For E. coli AG100A and AG100, 10 μl of total protein extracts and 25 μl of nickel affinity fractions were used. The position of Erm(44)-RGS-His6 on the gel is indicated with an asterisk. Prestained peqGOLD protein marker IV molecular size markers were used.