Bacterial strains genomics

The plasmids and operons described above represent the most studied ones, but probably constitute a small fraction of the catabolic operons in bacteria. In one study, 43 bacterial strains (mostly Pseudomonas spp.) from different sources, shown to possess the ability to degrade aromatic and PAHs, were hybridized with probes of NAH and TOL plasmids as well as with genomic DNA of bacteria known to degrade a wide variety of PAHs. Only 14 strains that mineralized naphthalene and phenanthrene showed homology to one of the probes. The remaining isolates mineralized and/or oxidized various PAHs and hybridized with neither pure plasmids nor genomic DNA (Foght Westlake, 1991). 

A second approach exploits the information contained in genome and protein sequencing databases. The masses of a set of proteins from the bacterial strain under study are determined and used to search databases for protein molecular mass matching. This has been used as a method to differentiate B. subtilis and E. coli, two organisms that have completely sequenced genomes.34... 

SNPs and InDei (Insertion/deletion) are distributed equally over the total genome of animals, plants, fungi, and bacteria. They have very low mutation rates and therefore can be used for animal or plant species determination, identification of fungi or bacterial strains, proof of identity, and authenticity testing. Detection of SNPs can be carried out on both genomic and mitochondrial DNA. 

While a number of organisms have been investigated as potential hosts for the expression of elastin-mimetic polypeptide sequences, bacterial strains of E. coli remain the preferred cellular host for these experiments. Escherichia coli strains have a number of advantages for these applications, which include the availability of highly effective expression plasmids, the potential for introduction of genomic modifications, a well-characterized physiological response, simple... 

The cyanobacterial strain Anabaena variabilis PCC 29413 was maintained as described (3) on solid and liquid media supplemented with 10 mM HEPES pH 8.0. High CO2 cultures were stirred and bubbled with 2-5 % CO2 in air while low CO2 cultures were aerated with air alone (0.035 % CO2). The bacterial strains E.. coli HBlOl and JMlOl were maintained as described (4). Cyanobacterial genomic DNA and bacterial plasmid DNA was isolated essentially as described (5) with some modifications. Southern hybridization of restriction endonuclease fragments was performed with nitrocellulose membranes using P-labelled heterologous probes according to the manufacturer s specifications (S S). Total RNA isolation from Anabaena cells was performed as described (6) with some modifications. Northern hybridization was... 

---