Learn More
Intrinsic drug resistance in Mycobacterium tuberculosis limits therapeutic options for treating tuberculosis. The mycobacterial transcriptional regulator whiB7 contributes to intrinsic resistance by activating its own expression and many drug resistance genes in response to antibiotics. To investigate whiB7 activation, we constructed a GFP reporter to(More)
Gene clusters found in bacterial species classified as Streptomyces encode the majority of known antibiotics as well as many pharmaceutically active compounds. A site-specific recombination system similar to those that mediate plasmid conjugation was engineered to catalyze tandem amplification of one of these gene clusters in a heterologous Streptomyces(More)
Clinical isolates of Escherichia coli were found to host a multiplicity of plasmids. These were resolved from plasmid gel profiles, from the properties of various transconjugants and transformants of E. coli DH1, by the topoisomerase I relaxation of covalently closed circle plasmid DNA, by electron microscopy, and by the determination of their(More)
Tuberculosis therapeutic options are limited by the high intrinsic antibiotic resistance of Mycobacterium tuberculosis. The putative transcriptional regulator WhiB7 is crucial for the activation of systems that provide resistance to diverse antibiotic classes. Here, we used in vitro run-off, two-hybrid assays, as well as mutagenic, complementation and(More)
Cationic peptides possessing antibacterial activity are virtually ubiquitous in nature, and offer exciting prospects as new therapeutic agents. We had previously demonstrated that such peptides could be produced by fusion protein technology in bacteria and several carrier proteins had been tested as fusion partners including glutathione-S-transferase, S.(More)
A simple, high frequency chromosomal gene replacement method of general utility was developed for Salmonella enteritidis. This system uses an unstable, imperfectly segregating, temperature-sensitive replicon, pHSG415, as a carrier of the recombinant gene of interest. It also allows for site-specific replacement of chromosomal genes without the need for(More)
Salmonella enteritidis thin fimbriae, SEF14, were found to be restricted to S. dublin and the predominantly poultry-associated members of the Salmonella O-serogroup D1, S. enteritidis, S. berta, S. gallinarum and S. pullorum, when tested by Western and ELISA analysis from among 90 Salmonella isolates of 42 serovars, as well as from members of several(More)
Piscirickettsia salmonis is the aetiological agent of salmonid rickettsial septicaemia, an economically devastating rickettsial disease of farmed salmonids. Infected salmonids respond poorly to antibiotic treatment and no effective vaccine is available for the control of P. salmonis. Bacterin preparations of P. salmonis were found to elicit a dose-dependent(More)
The role of the RepA initiator protein in replication and copy-number control of pKL1, a small cryptic plasmid of Escherichia coli, was elucidated. The identified ori region encompasses a copy-number control element (cop) and an active single-strand initiation signal (ssi), n'-pasH, which were essential for efficient plasmid replication. The cop region also(More)
Salmonella enteritidis 27655-3b and a few diarrheagenic Escherichia coli strains produce morphologically and antigenically related, thin, aggregative fimbriae, collectively named GVVPQ fimbriae (S. K. Collinson, L. Emödy, T. J. Trust, and W. W. Kay, J. Bacteriol. 174:4490-4495, 1992). To determine whether GVVPQ fimbriae are common to Salmonella spp. and(More)