All organisms, including bacteria, need to be able to adapt quickly to changes in their environment in order to ensure their survival. An important step of regulation takes place at the level of RNA, what requires key players like Ribonucleases and RNA-binding proteins.

Ribonucleases (RNases) and RNA-binding proteins (RBPs) play a crucial role in all kingdoms of life and provide a level of regulation by catalyzing or influencing the degradation and maturation of RNA. RNases are mainly divided into two different groups, meaning that they catalyze the hydrolysis of RNA from the inside of the molecules (endoribonucleases) or the outside (exoribonucleases). Currently 21 ribonucleases in the well-studied soil bacterium Bacillus subtilis are known.

Here we present a hexameric nucleolytic enzyme which might hve a global role in cell differentiation in B. subtilis. Our protein of interest is described as ribonuclease and is characterized by its unique domain structure, containing a C-terminal OB domain (oligonucleotide binding) and a N-terminal HD (metal dependend phosphohydrolase) domain. The specific function of this RNase in B. subtilis is currently unknown.

Our preliminary in vivo and in vitro analysis of this hexameric enzyme indicate a regulatory role in cell differentiation in B. subtilis.