ISSN:
1365-2958
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
,
Medicine
Notes:
Rapid proteolysis plays an important role in regulation of gene expression. Proteolysis of the phage λ CII transcriptional activator plays a key role in the lysis-lysogeny decision by phage λ. Here we demonstrate that the E. coli ATP-dependent protease FtsH, the product of the host ftsH/hflB gene, is responsible for the rapid proteolysis of the CII protein. FtsH was found previously to degrade the heat-shock transcription factor σ32. Proteolysis of σ32 requires, in vivo, the presence of the DnaK-DnaJ-GrpE chaperone machine. Neither DnaK-DnaJ-GrpE nor GroEL-GroES chaperone machines are required for proteolysis of CII in vivo. Purified FtsH carries out specific ATP-dependent proteolysis of CII in vitro. The degradation of CII is at least 10-fold faster than that of σ32. Electron microscopy revealed that purified FtsH forms ring-shaped structures with a diameter of 6–7 nm.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2958.1997.4231796.x
Permalink
