Integrons can insert and excise antibiotic resistance genes on plasmids in bacteria by site-specific recombination. Class 1 integrons code for an integrase, IntI1 (337 amino acids in length), and are generally borne on elements derived from Tn5090, such as that found in the central part of Tn21. A second class of integron is found on transposon Tn7 and its relatives. We have completed the sequence of the Tn7 integrase gene, intI2, which contains an internal stop codon. This codon was found to be conserved among intI2 genes on three other Tn7-like transposons harboring different cassettes. The predicted peptide sequence (IntI2*) is 325 amino acids long and is 46% identical to IntI1. In order to detect recombination activity, the internal stop codon at position 179 in the parental allele was changed to a triplet coding for glutamic acid. The sequences flanking the cassette arrays in the class 1 and 2 integrons are not closely related, but a common pool of mobile cassettes is used by the different integron classes; two of the three antibiotic resistance cassettes on Tn7 and its close relatives are also found in various class 1 integrons. We also observed a fourth excisable cassette downstream of those described previously in Tn7. The fourth cassette encodes a 165-amino-acid protein of unknown function with 6.5 contiguous repeats of a sequence coding for 7 amino acids. IntI2*179E promoted site-specific excision of each of the cassettes in Tn7 at different frequencies. The integrases from Tn21 and Tn7 showed limited cross-specificity in that IntI1 could excise all cassettes from both Tn21 and Tn7. However, we did not observe a corresponding excision of the aadA1 cassette from Tn21 by IntI2*179E.

SummaryGenes borne on cassettes are mobile owing to sitespecific recombination systems called integrons, which have created various combinations of antibiotic resistance genes in R-plasmids. In these processes, the palindromic site, attC (59-base element), at cassette junctions has been proposed as being essential. Excised and circularized cassettes have been found to integrate with preference for an attI site at one end of the conserved sequence in integrons. In this work, we give evidence that recombination is possible in the absence of the highly organized attC sites between the more simply organized attI sites. Furthermore, at a very low frequency representing the background in our recombination assay, we observed cross-overs between attI and secondary sites. To characterize recombination excluding the attC sites, we have used naturally occurring attI variants and constructed mutants. The cross-over point was identified between a guanine and a thymine in attI using point mutations. Progressive deletions showed the extent of attI and identified two important regions in the conserved sequence 5Ј of the cross-over point. A region 27-36 bp 5Ј of attI influenced recombination with attC sites only, whereas a sequence 9-14 bp 5Ј of the cross-over point in attI was important for recombination with both attI and attC. Recombination between attI and secondary sites could allow fusion of the conserved sequence encoding the integron site-specific recombinase to new sequences.

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The concept of open government, having been promoted widely in the past 5 years, has promised a broader notion than e-government, as supposed to fundamentally transform governments to become more open and participative and collaborative. Unfortunately, this has not significantly enhanced a set of fundamental problems regarding e-government. One of the problems is that the underlying democratic ideology is rarely clearly expressed. In this paper, we have therefore constructed a framework for the analysis of open government from a democratic perspective, to explore the research foundation of open government and the types of research missing. We have looked closely at the notion of democracy in peer-reviewed journals on open government from 2009 to 2013, focusing on discussions of some fundamental issues regarding democracy and the type of solutions suggested. We have found that despite seemingly good intentions and an extensive rhetoric, there is still an apparent lack of adequate tools in which public deliberation and representation are addressed in any meaningful sense. There are two main important observations herein: (i) the rhetoric in the dominant discourse supports the concept of open government formulated by the Obama administration as transparency, participation, and collaboration, but in practice, the focus is predominantly on transparency and information exchange, while ignoring fundamental democratic issues regarding participation and collaboration, and (ii) the concept of the public is inadequately considered as a homogenous entity rather than a diversified group with different interests, preferences, and abilities.

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