Northern blot analysis led to the detection of 4 mRNA species of 4.9 kb, 3.6 kb, 3.6 kb, and 1.2 kb the first 2 species were heat inducible. Their presence upstream of the dnaK locus in L monocytogenes suggested a similar regulatory mechanism for the transcription initiated at the promoter, P1. The hrcA gene and a regulatory sequence, designated CIRCE (controlling inverted repeat of chaperone expression), play a role in the regulation of expression of the dnaK locus in response to heat shock in several gram-positive bacteria.

Analysis of the sequences revealed the consensus promoter sequences of gram-positive bacteria, P1 and P2 upstream of the hrcA and dnaJ, respectively. The transcription from S1 was heat inducible. Primer extension analysis revealed 3 transcription start sites-S1, S2, and S3-upstream of the hrcA, grpE, and dnaJ, respectively.

Molecular analysis of the locus identified 6 genes in the order hrcA, grpE, dnaK, dnaJ, orf35, and orf29.

ABSTRACT The complete dnaK operon of Listeria monocytogenes was isolated by chromosome walking using the previously cloned dnaK gene as a probe.

System shock 2 the many sequence