FIG. 5.

Formation of a heat-stable multimeric complex by P. alcaligenes XcpQ protein. Cellular proteins, heated for 10 min at 95°C prior to SDS-PAGE, were analyzed by immunoblotting with an antiserum directed against P. aeruginosa XcpQ. P. alcaligenes strain Ps93 and derivatives of P. aeruginosa xcpP to -Z deletion mutant DZQ40 containing either pLAFR3, pAX24 carrying the P. aeruginosa xcpP to -Z gene cluster, or pLAF600 carrying the P. alcaligenes xcpP to -Z gene cluster were grown on a plate (P) or in liquid medium (L). Proteins were separated on a gel containing 3 and 9% acrylamide in the stacking and running gels, respectively. c, multimeric complex of P. alcaligenes XcpQ; m, XcpQ monomer.