ENDOGENOUS ADP-RIBOSYLATION DURING DEVELOPMENT OF THE PROKARYOTE MYXOCOCCUS-XANTHUS

We examined endogenous ADP-ribosylation of proteins during the develop ment of the prokaryote Myxococcus xanthus. In vivo and in vitro endoge nous ADP-ribosylation of M. xanthus proteins was detected and the prof ile of modified proteins changed during development. Adenosine and nic otinamide inhibited ADP-ribosylation. Nicotinamide stimulated cells at low density to develop, in a manner similar to that previously observ ed with adenosine. Higher concentrations of nicotinamide inhibited agg regation. The in vivo effects of nicotinamide on developing M. xanthus cells correlate with its in vitro effects on ADP-ribosylation and the developmental profile of putative ADP-ribosylation substrates. These results suggest that ADP-ribosylation may regulate developmental prote ins in M. xanthus.