clpB, a novel member of the Listeria monocytogenes CtsR regulon, is involved in virulence but not in general stress tolerance.

Clp-HSP100 ATPases are a widespread family of ubiquitous proteins that occur in both prokaryotes and eukaryotes and play important roles in the folding of newly synthesized proteins and refolding of aggregated proteins. They have also been shown to participate in the virulence of several pathogens, including Listeria monocytogenes. Here, we describe a member of the Clp-HSP100 family of L.

Role of the Streptococcus agalactiae ClpP serine protease in heat-induced stress defence and growth arrest.

The main causes of microbial death after heat exposure are not well understood. Here, it is shown that the heat-shock protein ClpP plays a major role in heat-induced growth arrest in Streptococcus agalactiae. A mutant lacking the ClpP protease was more sensitive to the inhibitory effects of heat, salt and oxidative stress than the isogenic wild-type strain.

Yersinia pseudotuberculosis harbors a type IV pilus gene cluster that contributes to pathogenicity.

Fimbriae have been shown to play an essential role in the adhesion of pathogenic gram-negative bacteria to host cells. In the enteroinvasive bacterium Yersinia pseudotuberculosis, we characterized a previously unknown 11-kb chromosomal locus involved in the synthesis of type IV pili. The locus consists of 11 open reading frames forming a polycistronic unit and encoding putative Pil proteins, PilLMNOPQRSUVW.

Involvement of the N- and C-terminal domains of Mycobacterium tuberculosis KatG in the protection of mutant Escherichia coli against DNA-damaging agents.

The Mycobacterium tuberculosis KatG enzyme, like most hydroperoxidase I (HPI)-type catalases, consists of two related domains, each with strong similarity to the yeast cytochrome c peroxidase. The catalase-peroxidase activity is associated with the amino-terminal domain but currently no definite function has been assigned to the carboxy-terminal domain, although it may play a role in substrate binding. This paper reports another possible function of the KatG protein involving protection of the host cell against DNA-damaging agents.