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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