Phosphoenolpyruvate carboxylase (PEPC) in extracts of neisseria gonorrhoeae.

The enzymatic carboxylation of phosphoenolpyruvate by cell free extracts of Neisseria gonorrhoeae was examined and determined to be similar to the reaction catalysed by phosphoenolpyruvate carboxylase (PEPC). This is shown by the irreversibility of the reaction and nucleotide independency. The enzyme extract was found to have some characteristics different from the other bacterial PEPC's reported. The enzyme extract showed catalytic activity in the presence of cobalt ions as well as magnesium and manganese ions, was not inhibited by succinate in fresh extracts, and displayed a low Michaelis constant for bicarbonate (0.59 mM) as compared to other PEPC's. The significance of this low Michaelis constant is discussed with respect to the growth of the organism and the importance of this enzyme to protein and nucleic acid synthesis.