Quaternary structure and biochemical properties of mycobacterial RNase E/G

Mirijam-Elisabeth Zeller , Agnes Csanadi , Andras Miczak , Thierry Rose , Thierry Bizebard , Vladimir Kaberdin (1)

1 Microbiology and Immunobiology

The RNase E/G family of endoribonucleases plays the central role in numerous posttranscriptional mechanisms in E. coli and, presumably, in other bacteria including human pathogens. To learn more about specific properties of RNase E/G homologues from pathogenic Gram-positive bacteria, a polypeptide comprising the catalytic domain of M. tuberculosis RNase E/G (MycRne) was purified and characterized in vitro. Here, we show that affinity-purified MycRne has a propensity to form di- and tetramers in solution and possesses an endoribonucleolytic activity, which is dependent on the 5´-phosphorylation status of RNA. Our data also indicate that the cleavage specificities of the M. tuberculosis RNase E/G homologue and its E. coli counterpart are only moderately overlapping and reveal a number of sequence determinants within MycRne cleavage sites that differentially affect the efficiency of cleavage. Finally, we demonstrate that, similar to E. coli RNase E, MycRne is able to cleave in an intercistronic region of the putative 9S precursor of 5S rRNA, thus suggesting a common function for RNase E/G homologues in rRNA processing.

Mots clés: Life Sciences

Mirijam-Elisabeth Zeller, Agnes Csanadi, Andras Miczak, Thierry Rose, Thierry Bizebard, et al.. Quaternary structure and biochemical properties of mycobacterial RNase E/G. Biochemical Journal, 2007, 403 (1), pp.207-215. ⟨10.1042/BJ20061530⟩. ⟨hal-00478684⟩