Question

Why is genetic recombination important for bacteria?

Answer 1

Hint: Genetic recombination is the process of rearrangement of DNA sequences by the breakage and rejoining of chromosomes or chromosome segments. Genetic recombination is a programmed feature of meiosis in most sexually reproducing organisms, in this it ensures the proper segregation of chromosomes as the frequency of recombination is approximately proportional to the physical distance between markers, it provides the basis for genetic mapping. Bacterial transformation is carried out by various interacting bacterial gene products.

Complete solution:
Bacteria do not have sexual reproduction in the similar way as the eukaryotes do. As bacteria do not have- no alternation of diploid and haploid generation, no gamete, no meiosis, so sexual reproduction takes place by genetic recombination. It has three mechanisms: transformation, conjugation, and transduction.

1. Transformation: transformation is defined as the genetic alteration of a cell resulting from the direct uptake and incorporation of exogenous genetic material from its surroundings through the cell membrane.

2. Conjugation: The transfer of genetic material between two bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells is called bacterial conjugation. This takes place through a pilus. This method of reproduction is a parasexual mode of reproduction.

3. Transduction: It is defined as a process of genetic recombination in bacteria in which genes from a host cell (a bacterium) are incorporated into the genome of a bacteriophage virus and then carried to another host cell when the bacteriophage initiates the next cycle of infection.

So, Genetic recombination ensures the proper segregation of chromosomes as the frequency of recombination is approximately proportional to the physical distance between markers, it provides the basis for genetic mapping. It also helps in providing DNA repair capability which facilitates survival of the infecting bacterial pathogen. Bacterial transformation is carried out by various interacting bacterial gene products.

Note:
Genetic recombination includes various different types of DNA rearrangements and underlying molecular processes. Meiotic recombination is an example of a reaction that involves DNA sequences that are paired and homologous over very extended lengths; this type of process is termed general, legitimate, or homologous recombination.