Disease relevance of tnpR

• In order to obtain stable Hfr donor strains of Pseudomonas aeruginosa PAO, we constructed a derivative of an RP1 (ts) plasmid, pME134, which was defective in the resolvase gene (tnpR) of transposon Tn801 [1].
• The SIVET lysogen has a defective H-19B prophage encoding the TnpR resolvase gene downstream of the phage PR promoter and a cat gene with an inserted tet gene flanked by targets for the TnpR resolvase [2].

High impact information on tnpR

• A putative binding site may be located in the N-terminal portion of the TnpR (resolvase) structural gene sequences [3].
• To extend the utility of the reporter gene fusion approach to such studies, we have constructed a gene expression reporter cassette that permits the generation of transcriptional fusions to tnpR encoding resolvase, a site-specific recombinase of the transposable element gamma delta [4].
• The site at which the recombination occurs, res, lies between the tnpA and tnpR genes [5].
• In order to determine the extent of the res site we have constructed in vitro a series of deletions that terminate within the tnpA-tnpR intergenic region, and have analyzed their effect on site-specific recombination [5].
• The gamma delta resolvase, product of the transposon's tnpR gene, mediates a site-specific recombination between two copies of gamma delta directly repeated on the same replicon [5].

Biological context of tnpR

• It involved the construction of a plasmid containing copies of res (Tn501) and res (Tn1721) in direct orientation and tnpR-mediated intramolecular recombination between the two homologous (but non-identical) sites [6].
• The protein was characterized by amino acid sequence studies (which showed that an open-reading frame previously identified by DNA sequencing had been correctly assigned to the tnpR gene) and by molecular weight measurements (which demonstrated that the only active for of the protein in solution was dimeric) [7].
• Resolvase, the product of tnpR, catalyses site-specific recombination at res, a 186 base pair (bp) sequence located adjacent to tnpR at one end of the homology region [6].

Associations of tnpR with chemical compounds

• Tn1739tnpR is a derivative of Tn1721 with a chloramphenicol-resistance-encoding gene (CmR), the lambda cI repressor gene, and a further copy of the resolvase-encoding tnpR gene under control of the tac promoter [8].

Other interactions of tnpR

• We also examined the ability of various transposons, assumed to be closely related, to complement the tnpA and tnpR mutations of Tn2603 [9].

References