Send to

Choose Destination
Biosci Biotechnol Biochem. 2007 Jan;71(1):158-64. Epub 2007 Jan 7.

RNase E is required for induction of the glutamate-dependent acid resistance system in Escherichia coli.

Author information

Department of Bioengineering, Tokyo Institute of Technology, Japan.


The Escherichia coli RNase E is an essential endoribonuclease involved in processing and/or degradation of rRNAs, tRNAs, and non-coding small RNAs as well as many mRNAs. It is known that RNase E activity is somehow regulated by an RNA-binding protein Hfq, at least in some cases. We searched for proteins that showed changes in expression in both hfq::cat and rne-1 mutant cells as compared with the wild type, and found that a protein band of 49-kDa decreased in these mutant cells at 42 degrees C, the restrictive temperature for rne-1. N-terminal amino acid sequencing identified it as a mixture of GadA and GadB, two isozymes of glutamate decarboxylase involved in glutamate-dependent acid resistance. The rne-1 mutant as well as the hfq mutant showed decreased survival under acidic conditions (pH 2.5). Hfq is known to regulate the expression of GadA/B in RpoS- and GadY small RNA-dependent ways. We examined the expression of these two regulators in rne-1 mutant cells. In the mutant cells, the induction of GadY was defective at 42 degrees C, but the expression of RpoS was normal. These results indicate that RNase E is required for induction of the glutamate-dependent acid resistance system in a RpoS-independent manner.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Taylor & Francis Icon for J-STAGE, Japan Science and Technology Information Aggregator, Electronic
Loading ...
Support Center