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Bacterial genetics. Gram-positive bacteria transform DNA using a transformasome complex. Figure 9.1. Gene Transfer by Conjugation. Conjugation is the transfer of DNA from one bacterium to another, following cell-to-cell contact.
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Gram-positive bacteria transform DNA using a transformasome complex. Figure 9.1
Gene Transfer by Conjugation Conjugation is the transfer of DNA from one bacterium to another, following cell-to-cell contact. - It is typically initiated by a special pilus protruding from the donor cell. Figure 9.2
An integrated F-factor can excise from the chromosome. - Aberrant excision results in an F′ factor or F′ plasmid,which carries chromosomal genes. Figure 9.5
Hfr leu+ thr+pro+lac+bio+Sms X F- leu- thr-pro-lac-bio-SmR What medium should we use to obtain 1. leu+ transconjugants 2. pro+ transconjugants 3. lac+ transconjugants
Hfr leu+ thr+pro+lac+bio+Sms X F- leu- thr-pro-lac-bio-SmR 1. leu+ transconjugants 2. pro+ transconjugants 3. lac+ transconjugants What are the map positions of leu, pro, and lac?
Generalized Transduction Figure 9.7
Specialized Transduction Figure 9.8
Generalized Recombination Figure 9.14
IS elements transfer by one of 2 mechanisms: - Replicative or nonreplicative transposition Mobile Genetic Elements Figure 9.31