Format

Send to:

Choose Destination
See comment in PubMed Commons below
Microbiology. 2008 Dec;154(Pt 12):3649-58. doi: 10.1099/mic.0.2008/020487-0.

The proteolytic activity of the HtrA (DegP) protein from Escherichia coli at low temperatures.

Author information

  • 1University of Gdansk, Department of Biochemistry, KÅ‚adki 24, 80-822 Gdansk, Poland. glonek@biotech.ug.gda.pl

Abstract

The HtrA (DegP) protein from Escherichia coli is a periplasmic protease whose function is to protect cells from the deleterious effects of various stress conditions. At temperatures below 28 degrees C the proteolytic activity of HtrA was regarded as negligible and it was believed that the protein mainly plays the role of a chaperone. In the present work we provide evidence that HtrA can in fact act as a protease at low temperatures. Under folding stress, caused by disturbances in the disulfide bond formation, the lack of proteolytic activity of HtrA lowered the survival rates of mutant strains deprived of a functional DsbA/DsbB oxidoreductase system. HtrA degraded efficiently the unfolded, reduced alkaline phosphatase at 20 degrees C, both in vivo and in vitro. The cleavage was most efficient in the case of HtrA deprived of its internal S-S bond; therefore we expect that the reduction of HtrA may play a regulatory role in proteolysis.

PMID:
19047732
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Ingenta plc
    Loading ...
    Write to the Help Desk