Resolution of 5-oxo-L-prolinase into a 5-oxo-L-proline-dependent ATPase and a coupling protein.
5-Oxo-L-prolinase catalyzes a reaction in which the endergonic cleavage of 5-oxo-L-proline to form L-glutamate is coupled to the exergonic cleavage of ATP to ADP and Pi. In the present research, the enzyme present in a strain of Pseudomonas putida isolated from soil by enrichment culture was found to be composed of two protein components. Neither component alone could catalyze the 5-oxoprolinase reaction, but the reaction was effectively catalyzed when they were mixed. One component (A) exhibited 5-oxo-L-proline-dependent ATPase activity indicating that Component A can interact with both ATP and 5-oxo-L-proline. The other component (coupling protein; B) does not exhibit ATPase activity nor is there evidence that it binds 5-oxo-L-proline. The findings are consistent with (but do not prove) the hypothesis that the Component A catalyzes an initial step in the reaction which involves 5-oxoproline and ATP, such as phosphorylation of 5-oxoproline. The coupling protein (B) may function as a catalyst that converts a phosphorylated form of 5-oxoproline to glutamate, or it might alter the conformation of Component A so as to facilitate the reaction.
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000581:Amidohydrolases / Q000302:isolation & purification*; D005971:Glutamates / Q000096:biosynthesis; D018698:Glutamic Acid; D007700:Kinetics; D011549:Pseudomonas / Q000201:enzymology*; D011752:Pyroglutamate Hydrolase / Q000302:isolation & purification* / Q000378:metabolism; D011760:Pyrrolidinones / Q000378:metabolism*; D011761:Pyrrolidonecarboxylic Acid / Q000378:metabolism*
D005971:Glutamates; D011760:Pyrrolidinones; D018698:Glutamic Acid; D000255:Adenosine Triphosphate; D000581:Amidohydrolases; D011752:Pyroglutamate Hydrolase; D000251:Adenosine Triphosphatases; D011761:Pyrrolidonecarboxylic Acid