Conjugation is a sexual type of reproduction in bacteria in which there is transfer of genes between two bacteria by directly coming in contact with each other. The conjugation was first described by Lederberg and Tatum(1946) in E.coli and other species of Gram –negative bacteria . Till now it hasn’t been found to be discovered in Gram –positive bacteria.
In the conjugation process the bacteria which donate genes or DNA is called donor cell or male cell and the other which receive the genes or DNA is called receipient cell or female cell. Each male cell posses an additional double stranded circular piece of small DNAin cytoplasm which is called a plasmid or sex factor . The sex factor is 1/1000 th size of enogenote( normal bacterial chromosome). Till now according to Lederberg and Tatum three types of sex factors are known. They are named as
a) Fertility factor or F factor (FF)
b) Resistance factor or R-factor.(RF)
c) Colicin factor or Col-factor(CF)
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