Exam 2 Review

Question 1

Colonization factors for pseudomonas

Answer 1

Pili and adhesins

Question 2

Survival factors for pseudomonas

Answer 2

LPS, capsule and biofilm formation

Question 3

Factors that cause damage or spread

Answer 3

LPS and toxins, flagella motility and chemotaxis

Question 4

Regulatory factors

Answer 4

Sigma factors (algU), two component regulation, quorum sensing

Question 5

Two- component regulatory system

Answer 5

Senses chemokine, histidine kinase self phosphorylates, transfers to response regulator, controls flagellar rotation

Question 6

Alginate

Answer 6

A protective capsule secreted by P. Aeruginosa , protects against host defenses and antibiotics

Question 7

AlgU

Answer 7

Sigma factor that controls alginate production, usually sequestered by MucA, but freed by periplasmic protease

Question 8

MucA

Answer 8

Membrane protein that sequesters AlgU, cleaved by protease

Question 9

Biofilm formation steps

Answer 9

1. Attachment (Fla+, Pol+)
2. Stable binding, growth (Fla-, Pil-)
   3-4. Capsule synthesis (Alg+)
3. Ready for release (Fla+, Pil+)
4. Planktonic bacteria (motility and chemotaxis)

Question 10

Quorum sensing

Answer 10

Release of autoinducers to give bacteria an idea of what’s there

Question 11

6 main antibiotic targets

Answer 11

1. Cell wall synthesis
2. DNA replication
3. RNA synthesis
4. Protein synthesis
5. Folic acid synthesis
6. Membrane disruption

Question 12

Penicillin and vancomycin

Answer 12

Target cell wall synthesis (D-ala D-ala motif)

Question 13

Fluoroquinlones

Answer 13

Target DNA synthesis

Question 14

Rifamycin

Answer 14

Targets RNA synthesis (RNA pol)

Question 15

Tetracyclines, chloramphenicol

Answer 15

Targets protein synthesis

Question 16

Sulfonamides

Answer 16

Target folic acid synthesis

Question 17

Daptomycin

Answer 17

Gram positive membrane disruption

Question 18

Colistin

Answer 18

Gram negative membrane disruption

Question 19

Ways bacteria resist abx (5)

Answer 19

• Inactivating abx
• Modifying or replacing target
• Remove abx from cell (effluent pumps)
• Prevent uptake
• Develop persister populations

Question 20

Examples of horizontal gene transfer (3)

Answer 20

Transformation’

• Transduction
• Conjugation

Question 21

Plasmid

Answer 21

Self replicating circular DNA that can move between cells

Question 22

Transposons

Answer 22

Linear DNA that can move within a cell

Question 23

Phages

Answer 23

Viruses that attack bacteria

Question 24

Examples of mobile genetic elements (3)

Answer 24

• Plasmid
• Transposons
• Phages

Question 25

Transformation

Answer 25

Process by which competent bacteria acquires genes from environment, sensitive to DNAse, small pieces

Question 26

Transduction

Answer 26

When a phage carries a piece of DNA to another bacterial cell (generalized lytic or specific lysogenic)

Question 27

RecA

Answer 27

Protein that catalyze homologous recombination events

Question 28

Replicons

Answer 28

DNA elements capable of self replication (bacterial chromosomes and plasmids)

Question 29

Rep protein

Answer 29

Recruit DNA pol to initiate DNA replication

Question 30

Origin of replication (Ori)

Answer 30

Binding site on DNA for REP OriC- chromosome -OriV- Vegetative plasmid - OriR- R factor plasmid

Question 31

Tra operon

Answer 31

Set of genes that encode for the transfer apparatus the sex pilus, can be anywhere in cell

Question 32

oriT

Answer 32

Origin of transfer, must be on replicons to be transferred

Question 33

COnjugation

Answer 33

A process by which the transfer of genetic arterial from one bacterium to another through direct contact

Question 34

Transposase

Answer 34

Needed for a region to be Transposon

Question 35

IR

Answer 35

Inverse repeat, at each end of a transposon

Question 36

How do viruses produce multiple proteins (5)

Answer 36

- Segmented genome - Polyprotein -Nested mRNA Start and stop transcription - Alternative splicing

Question 37

Antigenic shift

Answer 37

Cell with multiple different viruses, genomes differently packaged

Question 38

Antigenic drift

Answer 38

Mutations arise. Leading to loss or gain of function