Laboratory strains of Escherichia coli containing plasmid pBR325 (or pBR322) were coincubated with a mobilizer strain of E. coli (containing the conjugative plasmid R100-1) and a recipient strain of bacteria. Bacterial strains isolated from raw wastewater or a plasmid-free E. coli laboratory strain served as recipients. Transfer of the pBR plasmid into the recipient strain occurred during a 25-...

infectious bursal disease (ibd) is an economically important viral disease of chickens with worldwide distribution which suppresses the immune system of young chickens. vp2 is the major host-protective protein of infectious bursal disease virus (ibdv). the encoding region of vp2 protein was pcr amplified from a plasmid containing a cdna fragment of large genomic segment of ibdv, strain d78. thi...

The efficient partitioning of the 2m m plasmid of Saccharomyces cerevisiae at cell division is dependent on two plasmid-encoded proteins (Rep1p and Rep2p), together with the cis-acting locus REP3 ( STB ). In addition, host encoded factors are likely to contribute to plasmid segregation. Direct observation of a 2m m–derived plasmid in live yeast cells indicates that the multiple plasmid copies a...

An ultraviolet radiation-sensitive derivative of Streptococcus faecalis strain JH2-2 was isolated and found to be deficient in recombination, using a plasmid-plasmid recombination system. The strain was sensitive to chemical agents which interact with deoxyribonucleic acid and also underwent deoxyribonucleic acid degradation after ultraviolet irradiation. Thus, the mutant has properties similar...

Plasmid-to-chromosome ratios in Enterobacteriaceae, upon interruption of protein synthesis by chloramphenicol, are either conserved or increased when measured by dye buoyant density centrifugation. We have found, on the other hand, that the effect of inhibition of protein synthesis on the amount of covalently closed circular deoxyribonucleic acid visualized by this method in two strains of Stre...

RSF1010 plasmid DNA was introduced into Pseudomonas putida and P. aeruginosa cells and maintained stably, suggesting the potential usefulness of this plasmid as a vector in Pseudomonas species. The number of copies of RSF1010 was 43 per chromosome equivalent in P. putida cells.

We describe a novel mechanism of site-specific recombination in the unicellular marine cyanobacterium Synechococcus sp. PCC7002. The specific recombination sites on the smallest plasmid pAQ1 were localized by studying the properties of pAQ1-derived shuttle-vectors. We found that a palindromic element, the core sequence of which is G(G/A)CGATCGCC, functions as a resolution site for site-specific...

Background & objective:  Tuberculosis (TB) remains a major cause of death around the world. Bacillus Calmette Guérin (BCG) is the only vaccine used in TB prevention that has a protective effect in children, but its effectiveness declines in adults. Design and development of new vaccines is the most effective way against TB. The aim of this study was to design and construc...