Regulation of chromosome replication in Bacillus subtilis: marker frequency analysis after amino acid starvation.

Marker frequency analysis of DNA isolated from amino acid-starved Bacillus subtilis cells shows that most chromosomes have not completed replication to the terminus. This finding agrees with earlier results concerning replication after amino acid starvation in this organism. The results are not compatible with regulation of chromosome replication at the initiation step only, and they suggest that a second regulatory circuit controls replication under conditions of amino acid starvation.