The prokaryotic genome

The prokaryotic genome is very economical in terms of size (there is little noncoding DNA), but even so it is packaged into the cell. Scaffold proteins enable the DNA to be compacted into the small volume of a bacterial cell. The E. coli DNA is over 1 mm in length (Prob. 7.32), yet it is packaged into a cell with a diameter in micrometers. 

Fig. 1.23 Sketch of the cross-section of superhelical DNA in a cell. Left DNA is dispersed throughout the cell. Right DNA is confined within the nucleoid phase [255]. Reprinted from C. L. Woldringh and T. Odijk in Organization of the Prokaryotic Genome, R. L. Charlebois Ed.). ASM Press, Amsterdam, Copyright 1999, with permission from ASM Press...

A question which needs to be answered is how similar is the prokaryote genome organization and function to that in eukaryotes ... 

The temporal genome organization of eukaryotes could have evolved from the functional organization of the prokaryotic genome. The temporal sequence of protein synthesis in prokaryotes occurs from a stable, polycistronic template which is determined by the linear sequence of cistrons (Ohtaka and Spiegelman, 1963). For instance, the enzymes for histidine synthesis are in a sequence which corresponds to the linear gene sequence in the histidine operon of Salmonella typhimurium. There is a 20 min period between the appearance of the first and last (tenth) enzymes. The data can be explained on the basis of the successive synthesis of individual mRNA s or on the successive synthesis of a polycistronic message. This... 

A. Replication-Associated Strand Asymmetries in Prokaryotic Genomes The Replicon model... 

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