- Saturday, January 1, 2000
- Published at:Not Found
- Some naturally occurring plasmids like ColEl and ColK have been found to harbor site-specific recombination sequences, the core regions of such sequences have shown 82% homology when so aligned. The high degree of homology was the basis for testing the possibility of recombination between them. The sequences were cloned in the vector pUC18 in opposite orientation and introduced into E.coli cells and the analysis of the DNA harvested from the transformed cells showed that the sequences had undergone recombination, such recombination, such recombination was of the site-specific mode. No sequence deletion was detected, as was the case with such sequences when they were in the same orientation, Interestingly the event of recombination in this case resulted in the inversion of the region located between the recombination sites of the two cloned fragments.
An-Najah University Journal for Research - Natural Sciences (A) ISSN: 1727-2114
Volume 14 , 2000, Pages: 105-116
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- Friday, January 1, 1999
- Published at:Not Found
- Albendazole is determined by differential-pulse adsorptive cathodic stripping voltammetry at a hanging mercury drop electrode using the reduction peak of its copper(II) complex at -0.28V at an accumulation potential 0.0V vs. Ag/AgCl electrode. The optimum conditions of pH, accumulation potential and accumulation time were studied. The calibration graph for the determination of albendazole was linear in the range 3.0X10-8 - 9X10-7M with a relative standard deviation of 2.8%. The detection limit was 1.0X10-8M after 180s accumulation at 0.0V. The effect of common excipients and metal ions on the peak height of albendazole was studied. The presence of Cu2+ ions forms a stable complex with albendazole which is strongly adsorbed at the mercury electrode surface. The method was applied to the determination of the drug in commercially available dosage forms.
Analytical Letters, Volume 32, Issue 15 1999 , pages 2965 - 2975
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- Friday, November 1, 1985
- Published at:Not Found
- We have identified and characterised a stability function encoded by the high copy plasmid ColK. The function is analogous to ColE1 cer and maximises stability by maintaining plasmids in the monomeric state. In vivo recombination between cer and ckr (which share more than 90% homology at the DNA sequence level) produced a functional hybrid. Sequence analysis of hybrids indicates that recombination involving cer and ckr is site-specific and occurs within a 35 bp region of DNA which contains palindromic symmetry.
Molecular and General Genetics MGG, Volume 201, Number 2 / November, 1985
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