Molecular analysis of the dnaK locus of Leptospira interrogans serovar Copenhageni
Analysis of the dnaK locus of Leptospira interrogans serovar Copenhageni identified four genes in the order hrcA, grpE, dnaK and dnaJ. This is the first time a homologue of hrcA has been identified in a spirochete. The hrcA gene and a regulatory sequence, designated CIRCE, play a significant role in...
Saved in:
Published in | Gene Vol. 216; no. 1; pp. 21 - 29 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Netherlands
Elsevier B.V
17.08.1998
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Analysis of the
dnaK locus of
Leptospira interrogans serovar Copenhageni identified four genes in the order
hrcA,
grpE,
dnaK and
dnaJ. This is the first time a homologue of
hrcA has been identified in a spirochete. The
hrcA gene and a regulatory sequence, designated CIRCE, play a significant role in the regulation of the
dnaK locus of several Gram+ organisms. Their presence upstream of
dnaK in
Leptospira suggested a similiar regulatory mechanism. Transcriptional analysis using reverse transcriptase–PCR demonstrated transcription of all four genes and indicated that
hrcA and
grpE were co-transcribed, as were
grpE and
dnaK. Whilst
hrcA,
grpE and
dnaK were closely linked on the chromosome, transcription terminators between
dnaK and
dnaJ and downstream of
dnaJ suggested that this latter gene exists in its own operon. Primer extension analysis located functional promoters upstream of
hrcA and
grpE; however, no evidence of a functional promoter could be found for
dnaJ. Moreover, transcripts encompassing the first three genes or the entire locus could not be demonstrated, suggesting that the four genes are regulated independently at the transcriptional level. These results indicate that the regulation of the
dnaK locus of
Leptospira differs somewhat from that observed in other organisms. |
---|---|
Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0378-1119 1879-0038 |
DOI: | 10.1016/S0378-1119(98)00329-1 |