Plasmids

Question 1

Define plasmids

Answer 1

closed circular or linear DNA molecules that replicate
independently from the bacterial chromosome

Question 2

Function of plasmids (2)

Answer 2

code for functions involved in their own life cycles and
for functions which affect the physiology of the host cell

Question 3

How does plasmid affect plant and animals?

Answer 3

pathogenicity in plants and animals

Question 4

plasmids are resistant to?

Answer 4

a wide spectrum of antimicrobial
compounds (antibiotics, heavy metals à R plasmids),
resistance to mutagenic agents (ethidium bromide), or
disinfectants (formaldehyde)

Question 5

size of plasmids

Answer 5

2kb to 100kb

Question 6

Plasmid from E. coli and its trait

Answer 6

ColE1, Bacteriocin whick kills E. coli

Question 7

Plasmid Tol trait and original source

Answer 7

Degradation of toluene and benzoic acid, Pseudomonas putida

Question 8

Plasmid for tumor initiation in plants and original source

Answer 8

Ti, Agrobacterium tumefaciens

Question 9

Plasmid pJP4 trait and original source

Answer 9

2, 4-D (dichlorophenoxyacetic acid) degradation, alcaligenes eutrophus

Question 10

Plasmid from Rhizobium meliloti and trait

Answer 10

pSym, nodulation on roots of legume plants

Question 11

Plasmid for antibiotic methylenomycin biosynthesis and original source

Answer 11

SCP1, Streptomyces coelicolor

Question 12

Plasmid RK2 trait and original source

Answer 12

Resistance to ampicillin, tetracycline , and kanamycin. Klebsiella aerogenes

Question 13

How was RK2 isolated?

Answer 13

isolated in connection with an outbreak of antibiotic-resistant Pseudomonas aeruginosa and Klebsiella aerogenes in Birmingham in 1969

Question 14

How was RK2 characterized?

Answer 14

a family of plasmids implicated in transfer of ampicillin resistance between bacterial strains

Question 15

Size of RK2, and carries what resistance genes?

Answer 15

60,000 bp. tetracycline, Beta-lactam antibiotic, and kanamycin resistance

Question 16

Plasmid with 117,000 bp

Answer 16

pCG86

Question 17

Define pCG86

Answer 17

isolated from a piglet with diarrhea; a hybrid plasmid – carries
enterotoxin genes (Ent plasmid) and resistance genes (R plasmid)

Question 18

Resistance genes carried by pCG86

Answer 18

Tetracycline, sulfanilamide, mercury resistance

Question 19

Arrange plasmid DNA Conformation types based on speed of electrophoresis migration. slowest to fastest.

Answer 19

circular dsDNA, Linear dsDNA, supercoiled dsDNA

Question 20

What are the plasmid DNA forms ? what causes damage of these DNA forms?

Answer 20

Form 1 supercoiled, Form 2 Nicked, Form 3 Linear. DNA can be nicked or broken by rough handling during the plasmid isolation