Article

Reconstitution and analysis of the multienzyme Escherichia coli RNA degradosome.

Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
Journal of Molecular Biology (Impact Factor: 3.91). 08/2008; 382(4):870-83. DOI: 10.1016/j.jmb.2008.07.059
Source: PubMed

ABSTRACT The Escherichia coli RNA degradosome is a multienzyme assembly that functions in transcript turnover and maturation of structured RNA precursors. We have developed a procedure to reconstitute the RNA degradosome from recombinant components using modular coexpression vectors. The reconstituted assembly can be purified on a scale that has enabled biochemical and biophysical analyses, and we compare the properties of recombinant and cell-extracted RNA degradosomes. We present evidence that auxiliary protein components can be recruited to the 'superprotomer' core of the assembly through a dynamic equilibrium involving RNA intermediaries. We discuss the implications for the regulation of RNA degradosome function in vivo.

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