Fig. 4

SDS-PAGE analysis of HN-Mptx expressed in E. coli, immunostained with anti-HN-tag and anti-Mptx antibodies. Each lane was loaded with 7.5 μg of total protein extracted from a 4 h (mid-exponential phase) cell culture of E.coli. M: marker protein with known molecular weight. Lanes indicated with minus are uninduced controls, lanes indicated with plus are loaded with protein extract from a cell culture induced with 80 ng/ml anhydrotetracycline