We have been studying the role that protein degradation plays in regulating gene expression and have continued with studies on the linkages between chromosome synthesis and partition of chromosomes during cell division. As part of continuing studies on the regulation of capsular polysaccharide synthesis by the unstable regulator RcsA, we have found that a downstream transacting regulator of rcsA synthesis encodes RNAs which apparently mediate the regulatory effect. Mutations in both the regulator and target will allow further characterization of the mode of regulation. Mutations in the putative phosphorylation site of RcsB support a role for phosphorylation in capsule regulation. We are investigating the role of the heat shock chaperone proteins in degradation of substrates of the Lon ATP-dependent protease and initiating studies on the recognition specificity of Lon. Studies on the role and regulation of the Clp energy- dependent protease have concentrated on developing strains for the tight regulation of Clp synthesis, and investigating the function of a newly discovered alternate regulatory subunit, ClpX.
