Azotobacter vinelandii small RNAs: Their roles in the formation of cysts and other processes

Abstract

Azotobacter vinelandii is a soil bacterium that undergoes differentiation to form cysts resistant to desiccation. Alginate, polyhydroxybutyrate (PHB) and alkylresorcinols (AR) are structural components of the cysts. The synthesis of these compounds has been shown to be under control of the Gac/Rsm signal transduction pathway. This pathway includes eight small non-coding RNAs (RsmZ1-7 and RsmY), and the translational repressor protein RsmA. Binding of RsmA to Rsm-RNAs inhibits its repressor activity. Here, we review and discuss the roles of sRNAs in the formation of cysts and other processes in A. vinelandii. We also report a search for genes encoding small RNAs in the A. vinelandii genome. Two new sRNAs potentially related to the control of cyst components synthesis were identified in this search.