The frequency of chimeric molecules as a consequence of PCR co-amplification of 16S rRNA genes from different bacterial species
Article Abstract:
The 16S rRNA sequences that are 99.7% similar form 30% chimeras during PCR co-amplification. The recombinant molecules are identified by oligonucleotide probes that detect exchanges between homologous chromosomes. The frequency of chimeric molecules formation decreases with a decrease in the homology of the genes, longer elongation periods, and low premature termination. The frequency increases with an increase in the complexity of the DNA sequence and is unaffected by DNA damage. The formation of the chimeras is more during the later stages of PCR amplification.
Publication Name: Microbiology
Subject: Biological sciences
ISSN: 1350-0872
Year: 1996
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Tn5041: a chimeric mercury resistance transposon closely related to the toluene degradative transposon Tn4651
Article Abstract:
A novel-type transposon Tn5041 (14876 bp) has been found in a bacterium Pseudomonas strain which, like the rest of the Tn3 family, has chimeric mercury resistance properties. It has 47 bp terminal inverted repeats and putative transposase which is similar to the toluene degradative transposon Tn4651. Its putative resolvase amino acid sequence is like site-specific recombinase enzymes from the integrase family.
Publication Name: Microbiology
Subject: Biological sciences
ISSN: 1350-0872
Year: 1997
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Selection and characterization of mercury-independent activation mutants of the Tn501 transcriptional regulator, MerR
Article Abstract:
MerR regulates the mercury-resistance (mer) operon of transposon Tn501. A method to select constitutive activator mutants, activating transcription in the absence of HgII, is presented. Strong mercury-independent activation required at least two mutations i the MerR protein. Activation was increased with a triple mutation, and each mutant protein resulted in further activation in the presence of HgII.
Publication Name: Microbiology
Subject: Biological sciences
ISSN: 1350-0872
Year: 1998
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