THE RPOS GENE OF ERWINIA-CAROTOVORA - GENE ORGANIZATION AND FUNCTIONAL EXPRESSION IN ESCHERICHIA-COLI

rpoS homologues were identified in several Erwinia species using Esche richia coli rpoS sequences as probes. The rpoS gene from Erwinia carot ovora was cloned and the deduced amino acid sequence had 91% identity to E. coli RpoS. The latter sigma factor regulates the stationary phas e inducible HPII catalase activity of E. coil. In an E. coli rpoS muta nt, the E. carotovora rpoS gene was also able to regulate synthesis of this catalase, The presence of a similar catalase in E, carotovora su ggests that the structural gene for this may be part of the rpoS 'regu lon' in Erwinia also. This study also showed that there are several di fferences in the gene organization of the rpoS region of the E. coli a nd E. carotovora chromosomes. (C) 1998 Federation of European Microbio logical Societies. Published by Elsevier Science B.V.