FA Bacterial Genetics

Question 1

Ability to take up naked DNA (i.e. from cell lysis) from environment (also known as “competence”)

Answer 1

transformation

Question 2

transformation is a feature especially of what three bacteria?

Answer 2

S pneumo
HiB
Neisseria
(FA says remember with SHiN…)

Question 3

transformation uses what kind of DNA?

Answer 3

any naked DNA

Question 4

How could you keep transformation from occurring?

Answer 4

Adding deoxyribouclease to environment will degrade naked DNA in medium –> no transformation seen.

Question 5

What contains the genes required for sex pilus and conjugation?

Answer 5

F+ plasmid

Question 6

What do you call a bacterium without the plasmid containing the genes required for sex pills and conjugation?

Answer 6

F-

Question 7

What is plasmid made out of?

Answer 7

dsDNA

Question 8

what happens during F+ x F-?

Answer 8

plasmid is replicated and transferred through pilus from F+ to F-. no chromosomal genes transferred.

Question 9

What do you call it when F+ plasmid becomes incorporated into bacterial chromosomal DNA

Answer 9

High frequency recombination (Hfr) cell.

Question 10

Replication of incorporated plasmid DNA may include

Answer 10

some franking chromosomal DNA

Question 11

what is Hfr x F-

Answer 11

Tranfer of plasmid and chromosomal genes

Question 12

Segment of DNA “jumps” (excision and reintegration) from one location to another (plasmid to chromosome or vice versa)

Answer 12

transposition

Question 13

When excision occurs during transposition, what may also be incorporated and transferred to another bacterium?

Answer 13

some flanking chromosomal DNA

Question 14

a “packaging” event in which lytic phage infects bacterium, leading to cleavage of bacterial DNA. Parts of bacterial chromosomal DNA may become packaged in viral capsid. Phage infects another bacterium, transferring those genes.

Answer 14

Generalized transduction

Question 15

an “excision” event in which lysogenic page infects bacterium; viral DNA incorporates into bacterial chromosome. When phage DNA is excised, flanking bacterial genes may be excised with it. DNA is packaged into phage viral capsid and can infect another bacterium.

Answer 15

Specialized transduction

Question 16

what type of phage is associated with generalized transduction?

Answer 16

lytic

Question 17

what type of phage is associated with specialized transduction?

Answer 17

lysogenic

Question 18

genes for the following 5 bacterial toxins can be encoded in a lysogenic phage and transferred via specialized transduction (ABCDE)

Answer 18

ShigA like toxin
Botulinum toxin (certain strains)
Cholera toxin
Diphtheria toxin
Erythrogenic toxin of Strep pyogenes

Question 19

What bacterium can acquire Tox gene via lysogenization by a temperate bacteriophage?

Answer 19

Cornebacterium dipheriae