Insights into anti-termination regulation of the hut operon in Bacillus subtilis: importance of the dual RNA-binding surfaces of HutP

摘要: The anti-termination protein, HutP, regulates the gene expression of hut (histidine utilization) operon Bacillus subtilis, by destabilizing terminator RNA located upstream coding region encoding l-histidine degradation enzymes. On basis biochemical, in vivo and X-ray structural analyses, we now report that HutP uses its dual RNA-binding surfaces to access two XAG-rich regions (sites I II) within mediate destabilization process. In this process, initiates at 5′-end mRNA binding first (site I) then accesses second II), downstream stable G-C-rich segment stem. By action, appears disrupt stem, thus prevents premature termination transcription preceding for histidine