Bacterium genome

PCR will soon have another application in our domain for the differentiation of strains of the same species. Random primers are used for the moment. In this case, the reactions amplify several zones of the bacterium genome. After electrophoresis, the amplification products furnish a profile that can be characteristic of the strain. The difficulty lies in finding the primers. The best adapted ones for recognizing strains must give a profile for each strain in a reproducible manner. Among the lactic bacteria in wine, this process has only been applied to strains of O. oeni. The main application is in monitoring selected bacteria for malolactic fermentation. 

Oda Y, SK Samanta, FE Rey, L Wu, X Liu, T Yan, J Zhou, CS Harwood (2005) Functional genomic analysis of three nitrogenase isoenzymes in the photosynthetic bacterium Rhodopseudomonas palustris. J Bacterial 187 7784-7794. 

The genome of the Helicobacterpylori bacterium is 1.6 million base pairs in size and encodes 1590 ORFs (Tomb et al., 1997). The comprehensive two-hybrid library screen performed with these ORFs differs from the yeast experiments described above in that the Gal4 activation domain library used consisted of over ten million random genomic fragments (Rain et al., 2001). Thus, the potential problem of full-size ORFs masking protein-protein interactions is reduced. A total of 261 ORFs were fused to the Gal4 DNA binding domain to create a set of baits. These ORFs... 

Bacteria, being procaryotic, do not show compartmentation of the biosynthetic processes. The genome of a bacterium relates directly to the cytoplasm of the cell. Transcription into mRNA can lead directly to translation, and the processes of transcription and translation are not carried out in separate organelles. Animal cells, being eucaryotic, show compartmentation of the transcription and translation processes. Transcription of the genome into mRNA occurs in the nucleus, whereas translation occurs in the cytoplasm. The messenger RNA in the eucaryote is usually modified by adding to it... 

Oliynyk, M., Samborskyy, M., Lester, J.B. et al. (2007) Complete genome sequence of the erythromycin-producing bacterium Saccharopolyspora erythraea NRRL23338. Nature Biotechnology, 25, 447-453. 

In the bacterium Penicillium chrysogenum the genomic PPTase is similar to others. When the gene was knocked out, the bacteria needed lysine to survive and no longer produced penicillin or pigmentation. However the bacterium still completed the syntheses of roquefortine, another mycotoxin, and fatty acids. This work suggests that the pptase gene is not needed for the synthesis of fatty acids and roquefortine in this species of bacteria. 

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