The Essential Features of Prokaryotic Replication

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This is nothing but duplication of the nuclear material contained in the nucleus of the cell, be it pro or eukaryotes. Replication is an essential phenomenon related to growth and division of the cell. Growth and division refer not simply to the accretion of biomolecules, but to the replication of an integrated pattern of functions and structures. The continuity of cellular structure is a necessary complement to the continuity of genetic information. This occurs through the process of replication (Burton and Engelkirk, 2001, 134-150).
Replication of the prokaryotic cells is a process central to the biological reproduction and morphogenesis. From that aspect, every cell including prokaryotic cells continuously is in a process looking forward to the next cycle of replication as long as favourable environments are available. Sometimes, the time required to replicate is too small to acknowledge. There are incidences where a whole colony of prokaryote E. coli may replicate in 20 minutes. Indeed, making two cells where there was one before is the only discernible purpose of all the cell’s metabolism, physiology and behaviour. This process thus involves production of cell constituents as long as energy and nutrients are available to accommodate to the need of replication. This again involves three processes, doubling of the volume and surface area by elongation at constant diameter, duplication of the genome and partitioning of the copies, and cytokinesis, division of the cytoplasm by the in-growth of a septum at the midpoint, followed by separation of the daughter cells (Harold, 2001, 99-102).
Structurally, prokaryotes are very simple cells when compared to eukaryotic cells, and yet they are able to carry on the necessary processes of life. Reproduction of prokaryotic cells is by binary fission-the simple division of one cell into two cells, following DNA replication and the formation of a separating membrane and cell wall. The prokaryotic chromosome usually consists of a single, long, supercoiled, circular DNA molecule, which serves as the control center of the bacterial cell. It is capable of duplicating itself, guiding cell division, and directing cellular activities. When a cell is preparing to divide, all the DNA molecules in the chromosomes of that cell must duplicate, thereby ensuring that the same genetic information is passed on to both daughter cells. This process is called DNA replication. It occurs by separation of the DNA strands and the building of complementary strands by the addition of the correct DNA nucleotides (Burton and Engelkirk, 2001, 151-162).

Figure 1: The Process of Replication

Figure 2: Bacterial Replication Wall Synthesis
The point on the molecule where DNA replication starts is called the replication fork. The most important enzyme required for DNA replication is DNA polymerase. The duplicated DNA of the chromosomes can then be separated during cell division, so that each daughter cell contains the same number of chromosomes, the same genes, and the same amount of DNA as in the parent cell. In bacteria, as in other walled cells, morphogenesis revolves around wall construction. Bacteria lack an internal