REGULATION OF ASPARTATE TRANSCARBAMOYLASE ACTIVITY IN PSEUDOMONAS-STUTZERI

The regulation of aspartate transcarbamoylase activity in crude extrac ts of the denitrifying bacterium Pseudomonas stutzeri ATCC 17588 was i nvestigated. Under saturating substrate concentrations, putative effec ters of this bacterial transcarbamoylase activity were screened at two concentrations and were found to negatively control its activity. Bot h phosphate and pyrophosphate were strongly inhibitory to the P. stutz eri transcarbamoylase activity. Of the ribonucleotides tested as effec ters, it was observed that ATP, UTP and GTP produced the greatest enzy me inhibition.