2llz
GhoS (YjdK) monomer
Structural highlights
FunctionGHOS_ECOLI Antitoxin component of a type V toxin-antitoxin (TA) system. Neutralizes the toxic effects of toxin GhoT by digesting ghoT transcripts in a sequence-specific manner (PubMed:22941047). In concert with GhoT is involved in reducing cell growth during antibacterial stress (PubMed:24373067). Overexpression leads to transcript level reduction of 20 other mRNAs involved in purine or pyrimidine synthesis and transport. Not seen to bind its own promoter DNA (PubMed:22941047).[1] [2] Publication Abstract from PubMedAmong bacterial toxin-antitoxin systems, to date no antitoxin has been identified that functions by cleaving toxin mRNA. Here we show that YjdO (renamed GhoT) is a membrane lytic peptide that causes ghost cell formation (lysed cells with damaged membranes) and increases persistence (persister cells are tolerant to antibiotics without undergoing genetic change). GhoT is part of a new toxin-antitoxin system with YjdK (renamed GhoS) because in vitro RNA degradation studies, quantitative real-time reverse-transcription PCR and whole-transcriptome studies revealed that GhoS masks GhoT toxicity by cleaving specifically yjdO (ghoT) mRNA. Alanine substitutions showed that Arg28 is important for GhoS activity, and RNA sequencing indicated that the GhoS cleavage site is rich in U and A. The NMR structure of GhoS indicates it is related to the CRISPR-associated-2 RNase, and GhoS is a monomer. Hence, GhoT-GhoS is to our knowledge the first type V toxin-antitoxin system where a protein antitoxin inhibits the toxin by cleaving specifically its mRNA. A new type V toxin-antitoxin system where mRNA for toxin GhoT is cleaved by antitoxin GhoS.,Wang X, Lord DM, Cheng HY, Osbourne DO, Hong SH, Sanchez-Torres V, Quiroga C, Zheng K, Herrmann T, Peti W, Benedik MJ, Page R, Wood TK Nat Chem Biol. 2012 Sep 2. doi: 10.1038/nchembio.1062. PMID:22941047[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
