Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.8 (polynucleotide phosphorylase)
 723 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The biofilm formation by Pseudomonas aeruginosa highly increases the bacterial resistance to antimicrobial agents and host immune clearance. The biofilm formation is positively regulated by two small RNAs, RsmY and RsmZ. Previously, we reported that mutation in the polynucleotide phosphorylase (PNPase) coding gene pnp increases the levels of RsmY/Z. However, in this study, we found that the biofilm formation is decreased in the pnp mutant, which is due to a defect in rhamnolipids production. The rhamnolipids production is regulated by the RhlI-RhlR quorum sensing system. We found that PNPase influences the translation of RhlI through its 5'-untranslated region (UTR) and identified that the sRNA P27 is responsible for the translational repression. In vitro translation experiments demonstrated that P27 directly represses the translation of the rhlI mRNA through its 5'UTR in an Hfq-dependent manner. Point mutations in the rhlI 5'UTR or P27, which abolish the pairing between the two RNAs restore the rhlI expression and rhamnolipids production as well as the biofilm formation in the pnp mutant. Overall, our results reveal a novel layer of regulation of the Rhl quorum sensing system by the sRNA P27.
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PMID:Identification of a small RNA that directly controls the translation of the quorum sensing signal synthase gene rhlI in Pseudomonas aeruginosa. 3110 66