Gene location - importance in genome design
The EU-funded BMC (Bacteria with multiple chromosomes: Interplay between genome architecture and cell physiology) project has coined the term 'positional genetics'. Describing the effect of gene location on the physiology of a bacterium rather than the function of a gene per se promises to provide yet another way of modulating gene expression. The BMC team studied Vibrio cholerae, mainly because the bacterium has two circular genes and the gene dosage and position can therefore be engineered relatively easily. Moreover, as the cause of cholera, the bacterium is an important pathogen on a global scale. Researchers developed recombineering tools that enabled precise relocation of ribosomal protein (RP) genes in the bacterium without altering its structure. The physiology of the microbe was then monitored. Increasing the distance between RP genes and their initial location resulted in slower growth rates. Relocation of the genes far away from the original locus impaired the ability of the pathogen to infect a host, in this case the fruit fly Drosophila. Bioengineering and biotech researchers and workers will be able to tune the growth rate of Vibrio using the genomic position of RP genes. Moreover, the research sheds light on the evolution of bacteria with multiple chromosomes. Targeting different genes in other bacterial models will give insight into genome organisation. Knowledge on genomic factors affecting growth rate would enable programming of bacterial growth, important in biotechnology and bioindustrial processes.
Keywords
Gene location, positional genetics, Vibrio cholerae, recombineering, ribosomal protein, bacterial growth, biotechnology
