compounds that inhibit these reaction are referred to as glutamine antagogists. Azaserine and 6-diazo-5-oxo-l-norleucine,which were first isolated from cultures of streptomyces, are very effective inhibitor of glutamine utilization since azaserine and DON inactivate the enzymes irreversibly
the enzymes irreversibly,glutamine will not reverse the effects of these two drugs