RNase J enzymes are metallo-hydrolases involved in RNA maturation, RNA recycling and govern gene expression in bacteria and catalyze both exo-nuclease and endo-nuclease activity. The catalytic activity of RNase J is regulated by multiple mechanisms which include oligomerization, conformational changes to aid substrate recognition and the metal cofactor at the active site. However, little is known of how RNase J paralogues differ in expression and activity. Here we describe structural and biochemical features of two Staphylococcus epidermidis RNase J paralogues RNase J1 and RNase J2. RNase J1 is a homo-dimer with exo-nuclease activity aided by two metal co-factors at the active site. RNase J2, on the other hand, has endo-nuclease activity, one metal ion at the active site and is predominantly a monomer. We note that the expression levels of these enzymes vary across Staphylococcal strains. Together, these observations suggest that multiple interacting RNase J paralogues could provide a strategy for functional improvisation utilizing differences in intracellular concentration, quaternary structure and distinct active site architecture despite overall structural similarity.

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Two variations of a generic architecture of fixed cellular rural network suitable for rural applications in developing countries are presented. Performance evaluation of the two architectures in terms of call blocking probability is carried out by using a simulation model of the networks. It is shown by simulation results that a combination of wired and wireless networks with channel borrowing for intervillage call traffic results in lower call blocking probability.