Figure 3

Lipoprotein processing of PhoA. A. Effect of globomycin on the processing of PhoA. Mycoplasma transformants were grown in broth without or with globomycin added, as indicated above each lane, and their proteins separated on 10 % SDS-polyacrylamide gels, Western transferred and immunostained using a MAb to AP. In cells grown in globomycin (25 μg/ml), and thus in which signal peptidase II was inhibited, a higher molecular weight band was seen, indicative of the presence of the prolipoprotein. In the absence of globomycin (0 μg/ml) the fully processed 47 kDa lipoprotein is seen. B. Radiolabelling of PhoA. M. gallisepticum cell proteins and pTAP transformed M. gallisepticum cells were radiolabelled with [¹⁴ C]palmitate and separated on 10 % SDS-polyacrylamide gels. The polyacrylamide gels were stained with Coomassie brilliant blue and autoradiographed or Western transferred and immunostained using a MAb to AP. Lanes 1, M. gallisepticum cells; 2, pTAP transformed cells. Panels CB, Coomassie brilliant blue stained; WB, Western transferred and immunostained; RL, radiolabelled and autoradiographed. The dark arrow indicates the 67 kDa VlhA protein and the open arrow indicates the 47 kDa protein.