L8 Bact. genetics

Question 1

Transformation

Answer 1

• naked DNA from one to another - need competence factor
• Stept, Haemophilus, Neisseria
• Rec. A takes the naked ssDNA and replaces homologous recombination of current cell

Question 2

Transduction

Answer 2

bacteriophage infects cell and makes new viruses

• some of the bact. DNA gets incorporated and so you get sharing of bacteria DNA to the new bacteria cell that the bacteriophage infects
• homologous recombination

Question 3

Conjugation

Answer 3

• Most COMMON horizontal gene transfer
• bacteria sex
• sex pilus on male - it adds to female and then turns it male
• need conjugative plasmid
• transfer of ssDNA into new cell. then both old and new replicate the plasmid to dsDNA

Question 4

Plasmids

Answer 4

• main reason for antibiotic resistance
• replicate independently of chromosome but need host proteins
• oriT- origin of transfer
• transfer genes have sex pili encoded
• COP - copy control gene -

Question 5

compatible plasmids

Answer 5

• so different that can exist and replicate in a cell without disturbing each other

Question 6

conjugative plasmids

Answer 6

encode for sex pilus - but once formed other plasmids and cross over too
- usually have resistance

Question 7

R-plasmids

Answer 7

• resistance - many have growing complexity cuz more integrons added all the time

Question 8

3 transposon genes and mech

Answer 8

• transposase - does the actual genes for transposon
• repressor - to control-
• usually conveys resistance or virulence
• replicative - copy/paste
• conservative - cut and past