Inactivation of isocitrate lyase during myxospore development in Myxococcus xanthus

The inactivation of isocitrate lyase which occurs during late stages of myxospore formation in Myxococcus xanthus was studied. Several findings are reported. (i) Protein synthesis is required over a specific time interval in order for isocitrate lyase inactivation to occur at a later time. (ii) Metabolic energy is required at all times during myxospore development if the inactivation is to occur. (iii) It was possible to inhibit protein turnover to a considerable extent without affecting the net loss in isocitrate lyase activity.