The r-poll gene functions as a multicopy suppressor for mutations in the chaperones, CbpA, DnaJ and DnaK, in Escherichia coli
نویسندگان
چکیده
The CbpA protein is an analog of the DnaJ molecular chaperone of Escherichiu coli. The &I./cbpAdouble-null mutant exhibits severe defects in cell growth, namely, a very narrow temperature range for growth. To gain insight into the functions of CbpA as well as DnaJ, we isolated a multicopy suppressor gene that permits this &XLcbpA _ mutant to grow normally at low temperatures. The suppressor gene was identified as rpoD, the gene that encodes the major o”. The biological implications of this finding are examined and discussed.
منابع مشابه
CbpA, a DnaJ homolog, is a DnaK co-chaperone, and its activity is modulated by CbpM.
The DnaK chaperone system, consisting of DnaK, DnaJ, and GrpE, remodels and refolds proteins during both normal growth and stress conditions. CbpA, one of several DnaJ analogs in Escherichia coli, is known to function as a multicopy suppressor for dnaJ mutations and to bind nonspecifically to DNA and preferentially to curved DNA. We found that CbpA functions as a DnaJ-like co-chaperone in vitro...
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