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== Major circular chromosome (nucleotide) ==
Bacterial [[DNA (nukleová kyselina)|DNA]] is found freely in the cytoplasm, it is not enveloped by a membrane, so we are not talking about the nucleus. It consists of one circular [[Chromosom|chromosome]]. It is in the so-called nucleolar region and is attached in one place to the cytoplasmic membrane '''(OriC)'''. This place is called the '''mesosome'''.

The DNA of the double helix is enclosed in superhelicity - physiological is negative, ie more loose, negative superhelicity is maintained by enzymes [[Topologie DNA|topoisomerases]] (I - releases, II - produces ATP with consumption). The double helix consists of about 3 Mbp with a length of about 1-2 mm (the degree of spiralization depends on the transcriptional activity of the genes that lie in the section). The size of the bacterial genome is species-specific, ranging from six to eight thousand genes.

The amount of protein around the chromosome is non-constant and depends on the intensity of [[Proteosyntéza|proteosynthesis]] (these are mainly [[DNA (nukleová kyselina)|DNA (nucleic acid)]] and [[RNA]] polymerase). The proportion of RNA around the chromosome depends on the number of [[Gen|genes]] currently transcribed. The rate of cell division depends on the frequency of replication initiations (a new one can start during another ongoing one).

During division, DNA attaches to the mesosome. DNA duplication is subject to negative regulation - dilution of the replication inhibitor in a growing cell volume. When DNA is damaged, the SOS regulatory system is activated. There is only one haploid chromosome in the resting non-growing cell, mRNA unmodified - high transcription rate.