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Sexduction...

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SEXDUCTION Sexduction is another process in bacteria resulting F-prime factor. It happens when an abnormal crossing over occurs in Integrated F-Factor in genome resulting a F-factor with additional genes called F-prime factor. Sexduction is realized by the F factor, which is released independently from a bacterial chromosome along with a fragment of the chromosome. During F sexduction, the factor and chromosome fragment pass into the recipient cell, whereas during ordinary conjugation the F factor, which is incorporated into a chromosome, very rarely passes into the recipient cell. As a result of sexduction, the cells acquire the properties of the donor cells, that is, the ability to effect both sexduction and the transfer of a bacterial chromosome during future conjugations. In other respects, sexduction is similar to ordinary conjugation transfer. The cells become diploids with respect to the genes contained in the transferred fragment and acquire the characteristic peculiar to diploids of interaction between homologous genes. The stability of fractional diploids varies with the size of the transferred chromosomal fragment. The probability of recombination between a fragment and the homologous portion of a chromosome increases with the increasing length of the fragment, usually resulting in the restoration of haploidy. Sexduction resembles specific transduction, except that sexduction is accomplished by means of the autonomous F factor and not by a temperate bacteriophage issued from a bacterial chromosome.

REFERENCES Hayes, W. Genelika bakterii i bakteriofagov. Moscow, 1965. (Translated from English.) Low, K. B. “Escherichia coli K-12 F-Prime Factors, Old and New.” Bacteriological Reviews, 1972, vol. 36, no. 4....