Allantoinase from Pseudomonas aeruginosa. Purification, properties and immunochemical characterization of its in vivo inactivation.

The catabolic enzyme allantoinase is rapidly inactivated in cells of Pseudomonas aeruginosa when the stationary phase of growth is reached. This process is irreversible since the protein synthesis inhibitor chloramphenicol completely blocked the reappearance of allantoinase activity that is observed when allantoin is added to stationary cells. Purified alloantoinase appeared to be a protein composed of four identical subunits with a molecular weight of 38,000. With antibodies raised against purified allantoinase it was found that allantoinase inactivation is accompanied by a parallel decrease in immunologically reactive material. This suggests that allantoinase inactivation is caused or followed by rapid proteolysis.